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agencies</span> </div> </a> <button aria-controls="toc-Regulatory_agencies-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Regulatory agencies subsection</span> </button> <ul id="toc-Regulatory_agencies-sublist" class="vector-toc-list"> <li id="toc-North_America" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#North_America"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.1</span> <span>North America</span> </div> </a> <ul id="toc-North_America-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Japan" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Japan"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.2</span> <span>Japan</span> </div> </a> <ul id="toc-Japan-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Europe" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Europe"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.3</span> <span>Europe</span> </div> </a> <ul id="toc-Europe-sublist" class="vector-toc-list"> <li id="toc-United_Kingdom" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#United_Kingdom"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.3.1</span> <span>United Kingdom</span> </div> </a> <ul id="toc-United_Kingdom-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-China" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#China"> <div class="vector-toc-text"> <span class="vector-toc-numb">3.4</span> <span>China</span> </div> </a> <ul id="toc-China-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Emission_control_system_design" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Emission_control_system_design"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Emission control system design</span> </div> </a> <ul id="toc-Emission_control_system_design-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Emissions_control" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Emissions_control"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Emissions control</span> </div> </a> <button aria-controls="toc-Emissions_control-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Emissions control subsection</span> </button> <ul id="toc-Emissions_control-sublist" class="vector-toc-list"> <li id="toc-Air_injection" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Air_injection"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.1</span> <span>Air injection</span> </div> </a> <ul id="toc-Air_injection-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Exhaust_gas_recirculation" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Exhaust_gas_recirculation"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.2</span> <span>Exhaust gas recirculation</span> </div> </a> <ul id="toc-Exhaust_gas_recirculation-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Catalytic_converter" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Catalytic_converter"> <div class="vector-toc-text"> <span class="vector-toc-numb">5.3</span> <span>Catalytic converter</span> </div> </a> <ul id="toc-Catalytic_converter-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Evaporative_emissions_control" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Evaporative_emissions_control"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Evaporative emissions control</span> </div> </a> <ul id="toc-Evaporative_emissions_control-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Remote_sensing_emission_testing" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Remote_sensing_emission_testing"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>Remote sensing emission testing</span> </div> </a> <button aria-controls="toc-Remote_sensing_emission_testing-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Remote sensing emission testing subsection</span> </button> <ul id="toc-Remote_sensing_emission_testing-sublist" class="vector-toc-list"> <li id="toc-Use_of_emission_test_data" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Use_of_emission_test_data"> <div class="vector-toc-text"> <span class="vector-toc-numb">7.1</span> <span>Use of emission test data</span> </div> </a> <ul id="toc-Use_of_emission_test_data-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Alternative_fuel_vehicles" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Alternative_fuel_vehicles"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>Alternative fuel vehicles</span> </div> </a> <ul id="toc-Alternative_fuel_vehicles-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">10</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">11</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown 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class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Abgasfilter" title="Abgasfilter – German" lang="de" hreflang="de" data-title="Abgasfilter" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Control_de_emisiones_vehiculares" title="Control de emisiones vehiculares – Spanish" lang="es" hreflang="es" data-title="Control de emisiones vehiculares" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-ha mw-list-item"><a href="https://ha.wikipedia.org/wiki/Kula_da_hayaki_na_motoci" title="Kula da hayaki na motoci – Hausa" lang="ha" hreflang="ha" data-title="Kula da hayaki na motoci" data-language-autonym="Hausa" data-language-local-name="Hausa" class="interlanguage-link-target"><span>Hausa</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Kendali_emisi_kendaraan" title="Kendali emisi kendaraan – Indonesian" lang="id" hreflang="id" data-title="Kendali emisi kendaraan" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E8%87%AA%E5%8B%95%E8%BB%8A%E6%8E%92%E5%87%BA%E3%82%AC%E3%82%B9%E8%A6%8F%E5%88%B6" title="自動車排出ガス規制 – Japanese" lang="ja" hreflang="ja" data-title="自動車排出ガス規制" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-sq mw-list-item"><a href="https://sq.wikipedia.org/wiki/Kontrolli_i_emetimeve_t%C3%AB_automjeteve" title="Kontrolli i emetimeve të automjeteve – Albanian" lang="sq" hreflang="sq" data-title="Kontrolli i emetimeve të automjeteve" data-language-autonym="Shqip" data-language-local-name="Albanian" class="interlanguage-link-target"><span>Shqip</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Zni%C5%BEovanie_emisi%C3%AD_motorov%C3%BDch_vozidiel" title="Znižovanie emisií motorových vozidiel – Slovak" lang="sk" hreflang="sk" data-title="Znižovanie emisií motorových vozidiel" data-language-autonym="Slovenčina" data-language-local-name="Slovak" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Avgasrening" title="Avgasrening – Swedish" lang="sv" hreflang="sv" data-title="Avgasrening" data-language-autonym="Svenska" 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<div class="mw-indicators"> </div> <div id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Study of reducing the emissions produced by motor vehicles</div> <style data-mw-deduplicate="TemplateStyles:r1251242444">.mw-parser-output .ambox{border:1px solid #a2a9b1;border-left:10px solid #36c;background-color:#fbfbfb;box-sizing:border-box}.mw-parser-output .ambox+link+.ambox,.mw-parser-output .ambox+link+style+.ambox,.mw-parser-output .ambox+link+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+style+.ambox,.mw-parser-output .ambox+.mw-empty-elt+link+link+.ambox{margin-top:-1px}html body.mediawiki .mw-parser-output .ambox.mbox-small-left{margin:4px 1em 4px 0;overflow:hidden;width:238px;border-collapse:collapse;font-size:88%;line-height:1.25em}.mw-parser-output .ambox-speedy{border-left:10px solid #b32424;background-color:#fee7e6}.mw-parser-output .ambox-delete{border-left:10px solid #b32424}.mw-parser-output .ambox-content{border-left:10px solid #f28500}.mw-parser-output .ambox-style{border-left:10px solid #fc3}.mw-parser-output .ambox-move{border-left:10px solid #9932cc}.mw-parser-output .ambox-protection{border-left:10px solid #a2a9b1}.mw-parser-output .ambox .mbox-text{border:none;padding:0.25em 0.5em;width:100%}.mw-parser-output .ambox .mbox-image{border:none;padding:2px 0 2px 0.5em;text-align:center}.mw-parser-output .ambox .mbox-imageright{border:none;padding:2px 0.5em 2px 0;text-align:center}.mw-parser-output .ambox .mbox-empty-cell{border:none;padding:0;width:1px}.mw-parser-output .ambox .mbox-image-div{width:52px}@media(min-width:720px){.mw-parser-output .ambox{margin:0 10%}}@media print{body.ns-0 .mw-parser-output .ambox{display:none!important}}</style><table class="box-Lead_too_short plainlinks metadata ambox ambox-content ambox-lead_too_short" role="presentation"><tbody><tr><td class="mbox-image"><div class="mbox-image-div"><span typeof="mw:File"><a href="/wiki/File:Wiki_letter_w.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/en/thumb/6/6c/Wiki_letter_w.svg/40px-Wiki_letter_w.svg.png" decoding="async" width="40" height="40" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/6/6c/Wiki_letter_w.svg/60px-Wiki_letter_w.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/6/6c/Wiki_letter_w.svg/80px-Wiki_letter_w.svg.png 2x" data-file-width="44" data-file-height="44" /></a></span></div></td><td class="mbox-text"><div class="mbox-text-span">This article's <a href="/wiki/Wikipedia:Manual_of_Style/Lead_section#Length" title="Wikipedia:Manual of Style/Lead section">lead section</a> <b>may be too short to adequately <a href="/wiki/Wikipedia:Summary_style" title="Wikipedia:Summary style">summarize</a> the key points</b>.<span class="hide-when-compact"> Please consider expanding the lead to <a href="/wiki/Wikipedia:Manual_of_Style/Lead_section#Provide_an_accessible_overview" title="Wikipedia:Manual of Style/Lead section">provide an accessible overview</a> of all important aspects of the article.</span> <span class="date-container"><i>(<span class="date">August 2023</span>)</i></span></div></td></tr></tbody></table> <p><b>Vehicle emissions control</b> is the study of reducing the <a href="/wiki/Exhaust_gas" title="Exhaust gas">emissions</a> produced by <a href="/wiki/Motor_vehicle" title="Motor vehicle">motor vehicles</a>, especially <a href="/wiki/Internal_combustion_engine" title="Internal combustion engine">internal combustion engines</a>. The primary emissions studied include hydrocarbons, volatile organic compounds, carbon monoxide, carbon dioxide, nitrogen oxides, particulate matter, and sulfur oxides. Starting in the 1950s and 1960s, various regulatory agencies were formed with a primary focus on studying the vehicle emissions and their effects on human health and the environment. As the worlds understanding of vehicle emissions improved, so did the devices used to mitigate their impacts. The regulatory requirements of the Clean Air Act, which was amended many times, greatly restricted acceptable vehicle emissions. With the restrictions, vehicles started being designed more efficiently by utilizing various emission control systems and devices which became more common in vehicles over time. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Types_of_emissions">Types of emissions</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=1" title="Edit section: Types of emissions"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Emissions of many <a href="/wiki/Air_pollution" title="Air pollution">air pollutants</a> have been shown to have <a href="/wiki/Environmental_health" title="Environmental health">variety of negative effects</a> on <a href="/wiki/Public_health" title="Public health">public health</a> and the <a href="/wiki/Natural_environment" title="Natural environment">natural environment</a>. Emissions that are principal pollutants of concern include: </p> <ul><li><a href="/wiki/Hydrocarbon" title="Hydrocarbon">Hydrocarbons</a> (HC) – A class of burned or partially burned <a href="/wiki/Fuel" title="Fuel">fuel</a>, hydrocarbons are <a href="/wiki/Toxin" title="Toxin">toxins</a>. Hydrocarbons are a major contributor to <a href="/wiki/Smog" title="Smog">smog</a>, which can be a major problem in <a href="/wiki/Urban_area" title="Urban area">urban areas</a>. Prolonged exposure to hydrocarbons contributes to <a href="/wiki/Asthma" title="Asthma">asthma</a>, <a href="/wiki/Liver_disease" title="Liver disease">liver disease</a>, <a href="/wiki/Lung_disease" class="mw-redirect" title="Lung disease">lung disease</a>, and <a href="/wiki/Cancer" title="Cancer">cancer</a>. Regulations governing hydrocarbons vary according to type of <a href="/wiki/Engine" title="Engine">engine</a> and <a href="/wiki/Jurisdiction" title="Jurisdiction">jurisdiction</a>; in some cases, "non-<a href="/wiki/Methane" title="Methane">methane</a> hydrocarbons" are regulated, while in other cases, "total hydrocarbons" are regulated. Technology for one application (to meet a non-methane hydrocarbon standard) may not be suitable for use in an application that has to meet a total hydrocarbon standard. Methane is not directly toxic, but is more difficult to break down in fuel vent lines and a charcoal canister is meant to collect and contain fuel vapors and route them either back to the fuel tank or, after the engine is started and warmed up, into the air intake to be burned in the engine.</li> <li><a href="/wiki/Volatile_organic_compounds" class="mw-redirect" title="Volatile organic compounds">Volatile organic compounds</a> (VOCs) – Organic compounds which typically have a boiling point less than or equal to 250 °C; for example <a href="/wiki/Chlorofluorocarbon" title="Chlorofluorocarbon">chlorofluorocarbons</a> (CFCs) and <a href="/wiki/Formaldehyde" title="Formaldehyde">formaldehyde</a>.</li> <li><a href="/wiki/Carbon_monoxide" title="Carbon monoxide">Carbon monoxide</a> (CO) – A product of incomplete combustion, inhaled carbon monoxide reduces the blood's ability to carry oxygen; overexposure (<a href="/wiki/Carbon_monoxide_poisoning" title="Carbon monoxide poisoning">carbon monoxide poisoning</a>) may be fatal. (Carbon monoxide persistently binds to hemoglobin, the oxygen-carrying chemical in red blood cells, where oxygen (O<sub>2</sub>) would temporarily bind. The bonding of CO excludes O<sub>2</sub> and also reduces the ability of the hemoglobin to release already-bound oxygen, on both counts rendering the red blood cells ineffective. Recovery is by the slow release of bound CO and the body's production of new hemoglobin – a healing process – so full recovery from moderate to severe [but nonfatal] CO poisoning takes hours or days. Removing a person from a CO-poisoned atmosphere to fresh air stops the injury but does not yield prompt recovery, unlike the case where a person is removed from an asphyxiating atmosphere [i.e. one deficient in oxygen]. Toxic effects delayed by days are also common.)</li> <li>Nitrogen oxides (<a href="/wiki/NOx" title="NOx">NO<sub>x</sub></a>) – Generated when <a href="/wiki/Nitrogen" title="Nitrogen">nitrogen</a> in the air reacts with oxygen at the high temperature and pressure inside the engine. NO<sub>x</sub> is a precursor to smog and <a href="/wiki/Acid_rain" title="Acid rain">acid rain</a>. NO<sub>x</sub> includes NO and NO<sub>2</sub>.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> NO<sub>2</sub> is extremely reactive. NO<sub>x</sub> production is increased when an engine runs at its most efficient (i.e. hottest) operating point, so there tends to be a natural tradeoff between efficiency and control of NO<sub>x</sub> emissions. It is expected to be reduced drastically by use of <a href="/wiki/Emulsified_fuel" title="Emulsified fuel">emulsion fuels</a>.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup></li> <li><a href="/wiki/Particulates" title="Particulates">Particulate matter</a> – <a href="/wiki/Soot" title="Soot">Soot</a> or smoke made up of particles in the <a href="/wiki/Micrometre" title="Micrometre">micrometre</a> size range: Particulate matter causes negative health effects, including but not limited to <a href="/wiki/Respiratory_disease" title="Respiratory disease">respiratory disease</a> and <a href="/wiki/Cancer" title="Cancer">cancer</a>. Very fine particulate matter has been linked to cardiovascular disease.</li> <li><a href="/wiki/Sulfur_oxide" title="Sulfur oxide">Sulfur oxide</a> (SO<sub>x</sub>) – A general term for oxides of <a href="/wiki/Sulfur" title="Sulfur">sulfur</a>, which are emitted from motor vehicles burning fuel containing sulfur. Reducing the level of fuel sulfur reduces the level of sulfur oxides emitted from the tailpipe.</li></ul> <div class="mw-heading mw-heading2"><h2 id="History">History</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=2" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1251242444"><table class="box-More_citations_needed plainlinks metadata ambox ambox-content ambox-Refimprove" role="presentation"><tbody><tr><td class="mbox-image"><div class="mbox-image-div"><span typeof="mw:File"><a href="/wiki/File:Question_book-new.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/50px-Question_book-new.svg.png" decoding="async" width="50" height="39" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/75px-Question_book-new.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/99/Question_book-new.svg/100px-Question_book-new.svg.png 2x" data-file-width="512" data-file-height="399" /></a></span></div></td><td class="mbox-text"><div class="mbox-text-span">This article <b>needs additional citations for <a href="/wiki/Wikipedia:Verifiability" title="Wikipedia:Verifiability">verification</a></b>.<span class="hide-when-compact"> Please help <a href="/wiki/Special:EditPage/Vehicle_emissions_control" title="Special:EditPage/Vehicle emissions control">improve this article</a> by <a href="/wiki/Help:Referencing_for_beginners" title="Help:Referencing for beginners">adding citations to reliable sources</a>. Unsourced material may be challenged and removed.<br /><small><span class="plainlinks"><i>Find sources:</i> <a rel="nofollow" class="external text" href="https://www.google.com/search?as_eq=wikipedia&q=%22Vehicle+emissions+control%22">"Vehicle emissions control"</a> – <a rel="nofollow" class="external text" href="https://www.google.com/search?tbm=nws&q=%22Vehicle+emissions+control%22+-wikipedia&tbs=ar:1">news</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?&q=%22Vehicle+emissions+control%22&tbs=bkt:s&tbm=bks">newspapers</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.google.com/search?tbs=bks:1&q=%22Vehicle+emissions+control%22+-wikipedia">books</a> <b>·</b> <a rel="nofollow" class="external text" href="https://scholar.google.com/scholar?q=%22Vehicle+emissions+control%22">scholar</a> <b>·</b> <a rel="nofollow" class="external text" href="https://www.jstor.org/action/doBasicSearch?Query=%22Vehicle+emissions+control%22&acc=on&wc=on">JSTOR</a></span></small></span> <span class="date-container"><i>(<span class="date">November 2010</span>)</i></span><span class="hide-when-compact"><i> (<small><a href="/wiki/Help:Maintenance_template_removal" title="Help:Maintenance template removal">Learn how and when to remove this message</a></small>)</i></span></div></td></tr></tbody></table> <p>Throughout the 1950s and 1960s, various federal, state and local governments in the <a href="/wiki/United_States" title="United States">United States</a> conducted studies into the numerous sources of air pollution. These studies ultimately attributed a significant portion of air pollution to the automobile, and concluded air pollution is not bounded by local political boundaries. At that time, such minimal emission control regulations as existed in the U.S. were promulgated at the municipal or, occasionally, the state level. The ineffective local regulations were gradually supplanted by more comprehensive state and federal regulations. By 1967 the State of <a href="/wiki/California" title="California">California</a> created the <a href="/wiki/California_Air_Resources_Board" title="California Air Resources Board">California Air Resources Board</a>, and in 1970, the federal <a href="/wiki/United_States_Environmental_Protection_Agency" title="United States Environmental Protection Agency">United States Environmental Protection Agency</a> (EPA) was established. Both agencies, as well as other state agencies, now create and enforce emission regulations for automobiles in the United States. Similar agencies and regulations were contemporaneously developed and implemented in <a href="/wiki/Canada" title="Canada">Canada</a>, <a href="/wiki/Western_Europe" title="Western Europe">Western Europe</a>, <a href="/wiki/Australia" title="Australia">Australia</a>, and <a href="/wiki/Japan" title="Japan">Japan</a>. </p><p>The first effort at controlling pollution from automobiles was the <a href="/wiki/PCV_valve" class="mw-redirect" title="PCV valve">PCV (positive crankcase ventilation)</a> system. This draws crankcase fumes heavy in unburned hydrocarbons – a precursor to <a href="/wiki/Photochemical_smog" class="mw-redirect" title="Photochemical smog">photochemical smog</a> – into the engine's intake tract so they are burned rather than released unburned from the crankcase into the atmosphere. Positive crankcase ventilation was first installed on a widespread basis by law on all new <a href="/wiki/Model_year" title="Model year">1961-model</a> cars first sold in California. The following year, <a href="/wiki/New_York_(state)" title="New York (state)">New York</a> required it. By 1964, most new cars sold in the U.S. were so equipped, and PCV quickly became standard equipment on all vehicles worldwide.<sup id="cite_ref-Petersen_3-0" class="reference"><a href="#cite_note-Petersen-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p><p>The first legislated <a href="/wiki/Exhaust_system" title="Exhaust system">exhaust (tailpipe)</a> <a href="/wiki/Emission_standards" class="mw-redirect" title="Emission standards">emission standards</a> were promulgated by the State of California for 1966 model year for cars sold in that state, followed by the United States as a whole in model year 1968. Also in 1966, the first <a href="/wiki/Emission_test_cycle" title="Emission test cycle">emission test cycle</a> was enacted in the State of California measuring tailpipe emissions in PPM (parts per million). The standards were progressively tightened year by year, as mandated by the EPA. </p><p>By the 1974 model year, the <a href="/wiki/United_States_emission_standards" class="mw-redirect" title="United States emission standards">United States emission standards</a> had tightened such that the de-tuning techniques used to meet them were seriously reducing engine efficiency and thus increasing fuel usage. The new emission standards for 1975 model year, as well as the increase in fuel usage, forced the invention of the <a href="/wiki/Catalytic_converter" title="Catalytic converter">catalytic converter</a> for after-treatment of the exhaust gas. This was not possible with existing <a href="/wiki/Tetraethyllead" title="Tetraethyllead">leaded</a> <a href="/wiki/Gasoline" title="Gasoline">gasoline</a>, because the lead residue contaminated the platinum catalyst. In 1972, <a href="/wiki/General_Motors" title="General Motors">General Motors</a> proposed to the <a href="/wiki/American_Petroleum_Institute" title="American Petroleum Institute">American Petroleum Institute</a> the elimination of leaded fuels for 1975 and later model year cars.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (November 2016)">citation needed</span></a></i>]</sup> The production and distribution of unleaded fuel was a major challenge, but it was completed successfully in time for the 1975 model year cars. All modern cars are now equipped with catalytic converters to further reduce vehicle emissions. </p><p>Leading up to the 1981 model year in the United States, passenger vehicle manufactures were faced with the challenges in its history of meeting new emissions regulations, how to meet the much more restrictive requirements of the <a href="/wiki/Clean_Air_Act_(United_States)" title="Clean Air Act (United States)">Clean Air Act</a> (United States) per the 1977 amendment. For example: to meet this challenge, General Motors created a new "Emissions Control Systems Project Center" (ECS) first located at the AC Spark Plug Engineering Building in Flint, Michigan. Its purpose was to "Have overall responsibility for the design and development of the carborated and fuel injected closed loop 3-way catalyst system including related electronic controls, fuel metering, spark control, idle speed control, EGR, etc. currently planned through 1981."<sup id="cite_ref-GMtoday_4-0" class="reference"><a href="#cite_note-GMtoday-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-auto_5-0" class="reference"><a href="#cite_note-auto-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-auto1_6-0" class="reference"><a href="#cite_note-auto1-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> </p><p>In 1990, the Clean Air Act (CAA) was amended to help further regulate harmful vehicle emissions. In the amendment, vehicle fuel regulations became more stringent by limiting how much sulfur was allowed in diesel fuel. The amendments also required a procedural change for the creation of gasoline to ensure there are less emissions of hydrocarbons (HC), carbon monoxide (CO), nitrogen oxides (NO<sub>X</sub>), particulate matter (PM), and volatile organic compounds (VOCs). Changes made to the CAA also required the use of oxygenated gasoline to reduce CO emissions.<sup id="cite_ref-:1_7-0" class="reference"><a href="#cite_note-:1-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> </p><p>Throughout the years, the Environmental Protection Agency (EPA) continued to implement new regulations to reduce harmful emissions for vehicles. Some of the more important update standards are as follows. </p> <ul><li>1983: For areas with big pollution problems, Inspection and Maintenance programs were created, meaning vehicles would need to get tested for emissions.</li> <li>1985: Changed the allowable amount of gasoline to 0.1 grams per gallon.</li> <li>1991: Lowed the allowable emissions of HC and NOx for vehicle tailpipes</li> <li>1993: Began developing new vehicle technology to help triple the fuel economy in family sedans, thus reducing harmful emissions.</li> <li>1996: Lead in gasoline officially banned. New regulations created with intentions of innovating vehicle design to be cleaner for the environment and improving engine performance.</li> <li>1998: Diesel engine standards further increased in efforts to reduce ozone and PM emissions for various vehicles including industrial equipment.</li> <li>1999: Tailpipe emission standards are finalized, sulfur contents in gasoline are reduced, and various boats/other marine vehicles using diesel had reduced emission limits for NOx and PM.<sup id="cite_ref-:1_7-1" class="reference"><a href="#cite_note-:1-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup></li></ul> <div class="mw-heading mw-heading3"><h3 id="History_of_lead_in_gasoline">History of lead in gasoline</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=3" title="Edit section: History of lead in gasoline"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In 1922, lead was added to gasoline as an antiknock agent. It was not until 1969, nearly five decades later, that research began to show the negative health affects related to lead as a pollutant. Despite the plethora of negative health impacts discovered, no regulatory requirements were implemented to reduce lead levels in gasoline until 1983. Slowly, countries began banning use of lead in gasoline entirely from the years of 1986 to 2021. Japan was first to ban lead in gasoline in 1986, with North and South America following with nearly every country in the two continents banning lead by 1998. Africa was the latest to ban lead in gasoline with most countries banning in 2004 and 2005 and the last, Algeria, which didn’t ban it until 2021.<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Regulatory_agencies">Regulatory agencies</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=4" title="Edit section: Regulatory agencies"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The agencies charged with implementing exhaust <a href="/wiki/Emission_standard" title="Emission standard">emission standards</a> vary from jurisdiction to jurisdiction, even in the same country. For example, in the United States, overall responsibility belongs to the EPA, but due to special requirements of the State of California, emissions in California are regulated by the <a href="/wiki/California_Air_Resources_Board" title="California Air Resources Board">Air Resources Board</a>. In Texas, the <a href="/wiki/Texas_Railroad_Commission" class="mw-redirect" title="Texas Railroad Commission">Texas Railroad Commission</a> is responsible for regulating emissions from <a href="/wiki/Liquefied_petroleum_gas" title="Liquefied petroleum gas">LPG</a>-fueled rich burn engines (but not gasoline-fueled rich burn engines). </p> <div class="mw-heading mw-heading3"><h3 id="North_America">North America</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=5" title="Edit section: North America"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/California_Air_Resources_Board" title="California Air Resources Board">California Air Resources Board</a> – California, United States (most sources)</li> <li><a href="/wiki/Environment_Canada" class="mw-redirect" title="Environment Canada">Environment Canada</a> – Canada (most sources)</li> <li><a href="/wiki/United_States_Environmental_Protection_Agency" title="United States Environmental Protection Agency">Environmental Protection Agency</a> – United States (most sources)</li> <li><a href="/wiki/Texas_Railroad_Commission" class="mw-redirect" title="Texas Railroad Commission">Texas Railroad Commission</a> – Texas, United States (LPG-fueled engines only)</li> <li><a href="/wiki/Transport_Canada" title="Transport Canada">Transport Canada</a> – Canada (trains and ships)</li></ul> <div class="mw-heading mw-heading3"><h3 id="Japan">Japan</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=6" title="Edit section: Japan"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Ministry_of_Land,_Infrastructure,_Transport_and_Tourism" title="Ministry of Land, Infrastructure, Transport and Tourism">Ministry of Land, Infrastructure, Transport and Tourism</a> / Road Transport Bureau / Environmental Policy Division<sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup></li></ul> <div class="mw-heading mw-heading3"><h3 id="Europe">Europe</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=7" title="Edit section: Europe"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The <a href="/wiki/European_Union" title="European Union">European Union</a> has control over regulation of emissions in EU member states; however, many member states have their own government bodies to enforce and implement these regulations in their respective countries. In short, the EU forms the policy (by setting limits such as the <a href="/wiki/European_emission_standard" class="mw-redirect" title="European emission standard">European emission standard</a>) and the member states decide how to best implement it in their own country. </p> <div class="mw-heading mw-heading4"><h4 id="United_Kingdom">United Kingdom</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=8" title="Edit section: United Kingdom"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In the United Kingdom, matters concerning environmental policy are "devolved powers" so that some of the constituent countries deal with it separately through their own government bodies set up to deal with environmental issues: </p> <ul><li><a href="/wiki/Environment_Agency" title="Environment Agency">Environment Agency</a> – England and Wales</li> <li><a href="/wiki/Scottish_Environment_Protection_Agency" title="Scottish Environment Protection Agency">Scottish Environment Protection Agency</a> (SEPA) – Scotland</li> <li><a href="/wiki/Department_of_the_Environment_(Northern_Ireland)" title="Department of the Environment (Northern Ireland)">Department of the Environment</a> – Northern Ireland</li></ul> <p>However, many UK-wide policies are handled by the <a href="/wiki/Department_for_Environment,_Food_and_Rural_Affairs" title="Department for Environment, Food and Rural Affairs">Department for Environment, Food and Rural Affairs</a> (DEFRA) and they are still subject to EU regulations. </p><p>Emissions tests on <a href="/wiki/Diesel_fuel" title="Diesel fuel">diesel</a> cars have not been carried out during <a href="/wiki/MOT_test" title="MOT test">MOTs</a> in Northern Ireland for 12 years, despite being legally required.<sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="China">China</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=9" title="Edit section: China"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Ministry_of_Ecology_and_Environment" title="Ministry of Ecology and Environment">Ministry of Ecology and Environment</a> – Primary regulatory authority responsible for environmental protection, formulates policies, standards, and regulations which encompass vehicle emissions, and environmental impact assessments.<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup></li> <li><a href="/wiki/Ministry_of_Industry_and_Information_Technology" title="Ministry of Industry and Information Technology">Ministry of Industry and Information Technology</a> – Creates and establishes goals for new energy vehicles (NEV), and commercial vehicles. Also plays a role in creating national emissions standards for cars.<sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup></li> <li><a href="/wiki/State_Administration_for_Market_Regulation" title="State Administration for Market Regulation">State Administration for Market Regulation</a> – Responsible for market supervision and standardization in China. The State Administration for Market Regulation oversees the enforcement of vehicle emissions standards and ensures compliance by conducting inspections, testing, and quality control measures.<sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup></li> <li><a href="/wiki/National_Development_and_Reform_Commission" title="National Development and Reform Commission">National Development and Reform Commission</a> - Responsible for macroeconomic planning and formulating energy-related policies in China. The National Development and Reform Commission plays a role on fuel efficiency standards, promoting alternative fuels, and implementing energy-saving measures to reduce emissions from vehicles.<sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup></li> <li>China Automotive Technology & Research Center - An independent research institution commissioned by the Ministry of Industry and Information Technology, to research, develop and draft the standards for fuel consumption limits of motor vehicles.<sup id="cite_ref-:0_15-0" class="reference"><a href="#cite_note-:0-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup></li> <li><a href="/wiki/Ministry_of_Transport_of_the_People%27s_Republic_of_China" class="mw-redirect" title="Ministry of Transport of the People's Republic of China">Ministry of Transport of the People's Republic of China</a> - While it is unclear whether this ministry has legal authority on whether they can enforce these standards, the Ministry of Transport will not issue commercial licenses to any heavy-duty vehicles that don't meet fuel consumption requirements they have set.<sup id="cite_ref-:0_15-1" class="reference"><a href="#cite_note-:0-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup></li> <li>Provincial and Municipal Environmental Protection Bureaus - At the provincial and municipal level these Bureaus are responsible for enforcing regulations such as those related to vehicle emissions. These bureaus monitor compliance, conduct inspections, and impose penalties for non-compliance.</li></ul> <div class="mw-heading mw-heading2"><h2 id="Emission_control_system_design">Emission control system design</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=10" title="Edit section: Emission control system design"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>It was very important to system designers to meet the emission requirements using a minimum quantity of <a href="/wiki/Catalyst" class="mw-redirect" title="Catalyst">catalyst</a> material (<a href="/wiki/Platinum" title="Platinum">platinum</a> and/or <a href="/wiki/Palladium" title="Palladium">palladium</a>) due to cost and supply issues. The General Motors "Emissions Control Systems Project Center" was "to follow the operational plans established by previous (GM) Project Centers. Items unique to the "Emissions Control Systems Project Center" (were): </p> <ul><li>No Designers - all design work to be done at home divisions.</li> <li>Planning activity which will provide the official timing charts, component costs, allocations, etc.</li></ul> <p>The ("Emissions Control Systems Project Center") (had) seven tasks to perform, such that an emission system, which passes all existing Federal Emission and Fuel Economy legislation is put into production. </p><p>These are to work with the car divisions to: </p> <ol><li>Define hardware and system requirements.</li> <li>Develop design specifications for all hardware all hardware required.</li> <li>Review alternative designs and systems.</li> <li>Arrange to test and validate systems, which best suits the needs of all concerned.</li> <li>Monitor component design and release.</li> <li>Follow progress of divisional certification work.</li> <li>Keep management and divisions apprised of progress status.</li></ol> <p>The system implementation (was to) be phased in over three years. In the 1979 model year. California vehicles with 2.5, 2.8 and 3.5 liter engines will have a CLCC system. In 1980 model year, vehicles sold in California and 3.8 and 4.3 liter engines sold federally will have CLCC, and finally in the 1981 model year all passenger cars will have the system. California light and medium duty trucks may also use the c-4 system. While 1979 and 1980 systems are very similar, the 1981 system (2nd generation) will differ in that it may include additional engine control systems (i.e., electronic spark timing, idle speed control, etc.) </p><p>The Emission Control System under development has been designated C-4.This stands for Computer Controlled Catalytic Converter. The C-4 System encompasses Closed Loop Carburetor Control (CLCC) and Throttle Body Injection (TBI) systems.""<sup id="cite_ref-GMtoday_4-1" class="reference"><a href="#cite_note-GMtoday-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-auto_5-1" class="reference"><a href="#cite_note-auto-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-auto1_6-1" class="reference"><a href="#cite_note-auto1-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Emissions_control">Emissions control</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=11" title="Edit section: Emissions control"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Engine efficiency has been steadily improved with improved engine design, more precise ignition timing and <a href="/wiki/Electronic_ignition" class="mw-redirect" title="Electronic ignition">electronic ignition</a>, <a href="/wiki/Fuel_injection" title="Fuel injection">more precise fuel metering</a>, and <a href="/wiki/Electronic_control_unit" title="Electronic control unit">computerized engine management</a>. </p><p>Advances in engine and vehicle technology continually reduce the toxicity of exhaust leaving the engine, but these alone have generally been proved insufficient to meet emissions goals. Therefore, technologies to detoxify the exhaust are an essential part of emissions control. </p> <div class="mw-heading mw-heading3"><h3 id="Air_injection">Air injection</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=12" title="Edit section: Air injection"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Secondary_air_injection" title="Secondary air injection">Secondary air injection</a></div> <p>One of the first-developed exhaust emission control systems is secondary air injection. Originally, this system was used to inject air into the engine's exhaust ports to provide oxygen so unburned and partially burned hydrocarbons in the exhaust would finish burning. Air injection is now used to support the <a href="/wiki/Catalytic_converter" title="Catalytic converter">catalytic converter</a>'s oxidation reaction, and to reduce emissions when an engine is started from cold. After a cold start, an engine needs an air-fuel mixture richer than what it needs at <a href="/wiki/Operating_temperature" title="Operating temperature">operating temperature</a>, and the <a href="/wiki/Catalytic_converter" title="Catalytic converter">catalytic converter</a> does not function efficiently until it has reached its own operating temperature. The air injected upstream of the converter supports combustion in the exhaust headpipe, which speeds catalyst warmup and reduces the amount of unburned hydrocarbon emitted from the tailpipe. </p> <div class="mw-heading mw-heading3"><h3 id="Exhaust_gas_recirculation">Exhaust gas recirculation</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=13" title="Edit section: Exhaust gas recirculation"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Exhaust_gas_recirculation" title="Exhaust gas recirculation">Exhaust gas recirculation</a></div> <p>In the United States and Canada, many engines in 1973 and newer vehicles (1972 and newer in California) have a system that routes a metered amount of exhaust into the intake tract under particular operating conditions. Exhaust neither burns nor supports combustion, so it dilutes the air/fuel charge to reduce peak combustion chamber temperatures. This, in turn, reduces the formation of <a href="/wiki/NOx" title="NOx">NO<sub>x</sub></a>. </p> <div class="mw-heading mw-heading3"><h3 id="Catalytic_converter">Catalytic converter</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=14" title="Edit section: Catalytic converter"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Catalytic_converter" title="Catalytic converter">Catalytic converter</a></div> <p>The catalytic converter is a device placed in the exhaust pipe, which converts hydrocarbons, carbon monoxide, and NO<sub>x</sub> into less harmful gases by using a combination of platinum, palladium and rhodium as <a href="/wiki/Catalyst" class="mw-redirect" title="Catalyst">catalysts</a>.<sup id="cite_ref-16" class="reference"><a href="#cite_note-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> </p><p>There are two types of catalytic converter, a two-way and a three-way converter. Two-way converters were common until the 1980s, when three-way converters replaced them on most automobile engines. See the <a href="/wiki/Catalytic_converter" title="Catalytic converter">catalytic converter</a> article for further details. </p> <div class="mw-heading mw-heading2"><h2 id="Evaporative_emissions_control">Evaporative emissions control</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=15" title="Edit section: Evaporative emissions control"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">"EVAP" redirects here. The term may also refer to <a href="/wiki/Evaporation" title="Evaporation">Evaporation</a>.</div><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">See also: <a href="/wiki/Onboard_refueling_vapor_recovery" title="Onboard refueling vapor recovery">Onboard refueling vapor recovery</a></div><figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Aktivkohlefilter_205.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/c6/Aktivkohlefilter_205.JPG/220px-Aktivkohlefilter_205.JPG" decoding="async" width="220" height="293" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/c6/Aktivkohlefilter_205.JPG/330px-Aktivkohlefilter_205.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/c6/Aktivkohlefilter_205.JPG/440px-Aktivkohlefilter_205.JPG 2x" data-file-width="1536" data-file-height="2048" /></a><figcaption>Fuel vapor storage canister for a <a href="/wiki/Peugeot_205" title="Peugeot 205">Peugeot 205</a></figcaption></figure> <p>Evaporative emissions are the result of gasoline vapors escaping from the vehicle's fuel system. Since 1971, all U.S. vehicles have had fully sealed fuel systems that do not vent directly to the atmosphere; mandates for systems of this type appeared contemporaneously in other jurisdictions. In a typical system, vapors from the fuel tank and carburetor bowl vent (on carbureted vehicles) are ducted to canisters containing <a href="/wiki/Activated_carbon" title="Activated carbon">activated carbon</a>. The vapors are <a href="/wiki/Adsorbed" class="mw-redirect" title="Adsorbed">adsorbed</a> within the canister, and during certain engine operational modes fresh air is drawn through the canister, pulling the vapor into the engine, where it burns. </p> <div class="mw-heading mw-heading2"><h2 id="Remote_sensing_emission_testing">Remote sensing emission testing</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=16" title="Edit section: Remote sensing emission testing"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Some US states are also using a technology which uses <a href="/wiki/Infrared" title="Infrared">infrared</a> and <a href="/wiki/Ultraviolet" title="Ultraviolet">ultraviolet</a> light to detect emissions while vehicles pass by on public roads, thus eliminating the need for owners to go to a test center. Invisible light flash detection of <a href="/wiki/Exhaust_gas" title="Exhaust gas">exhaust gases</a> is commonly used in metropolitan areas,<sup id="cite_ref-17" class="reference"><a href="#cite_note-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> and becoming more broadly known in Europe.<sup id="cite_ref-18" class="reference"><a href="#cite_note-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Use_of_emission_test_data">Use of emission test data</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=17" title="Edit section: Use of emission test data"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Emission test results from individual vehicles are in many cases compiled to evaluate the emissions performance of various classes of vehicles, the efficacy of the testing program and of various other emission-related regulations (such as changes to fuel formulations) and to model the effects of auto emissions on public health and the environment. </p> <div class="mw-heading mw-heading2"><h2 id="Alternative_fuel_vehicles">Alternative fuel vehicles</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=18" title="Edit section: Alternative fuel vehicles"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Alternative_fuel_vehicle" title="Alternative fuel vehicle">Alternative fuel vehicle</a></div> <p>Exhaust emissions can be reduced by making use of clean vehicle propulsion. The most popular modes include <a href="/wiki/Hybrid_electric_vehicle" title="Hybrid electric vehicle">hybrid</a> and <a href="/wiki/Electric_vehicle" title="Electric vehicle">electric vehicles</a>. As of December 2020<sup class="plainlinks noexcerpt noprint asof-tag update" style="display:none;"><a class="external text" href="https://en.wikipedia.org/w/index.php?title=Vehicle_emissions_control&action=edit">[update]</a></sup>, China had the world's largest stock of highway legal plug-in electric passenger cars with 4.5 million units, representing 42% of the world's stock of plug-in cars.<sup id="cite_ref-EVOutlook2020_19-0" class="reference"><a href="#cite_note-EVOutlook2020-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-ChinaNEV2020_20-0" class="reference"><a href="#cite_note-ChinaNEV2020-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=19" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/AP_42_Compilation_of_Air_Pollutant_Emission_Factors" title="AP 42 Compilation of Air Pollutant Emission Factors">AP 42 Compilation of Air Pollutant Emission Factors</a></li> <li><a href="/wiki/Low_carbon_economy" class="mw-redirect" title="Low carbon economy">Low carbon economy</a></li> <li><a href="/wiki/On-board_diagnostics#OBD-I" title="On-board diagnostics">On-board diagnostics#OBD-I</a></li> <li><a href="/wiki/Ontario%27s_Drive_Clean" title="Ontario's Drive Clean">Ontario's Drive Clean</a></li> <li><a href="/wiki/Portable_Emissions_Measurement_System_(PEMS)" class="mw-redirect" title="Portable Emissions Measurement System (PEMS)">Portable Emissions Measurement System</a></li> <li><a href="/wiki/Roadway_air_dispersion_modeling" title="Roadway air dispersion modeling">Roadway air dispersion modeling</a></li> <li><a href="/wiki/Vehicle_inspection" title="Vehicle inspection">Vehicle inspection</a></li> <li><a href="/wiki/Phase-out_of_fossil_fuel_vehicles" title="Phase-out of fossil fuel vehicles">Phase-out of fossil fuel vehicles</a></li> <li><a href="/wiki/Non-exhaust_emissions" title="Non-exhaust emissions">Non-exhaust emissions</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=20" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist reflist-columns references-column-width" style="column-width: 30em;"> <ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation 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Retrieved <span class="nowrap">2020-05-06</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Journal+of+Cleaner+Production&rft.atitle=Policy+norms+and+proposed+ways+to+achieve+goals+of+Indian+vehicle+emission+program&rft.volume=208&rft.pages=1339-1346&rft.date=2019-01-20&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A158500168%23id-name%3DS2CID&rft.issn=0959-6526&rft_id=info%3Adoi%2F10.1016%2Fj.jclepro.2018.10.202&rft.aulast=Lathia&rft.aufirst=Rutvik&rft.au=Dadhaniya%2C+Sujal&rft_id=http%3A%2F%2Fwww.sciencedirect.com%2Fscience%2Farticle%2Fpii%2FS0959652618332244&rfr_id=info%3Asid%2Fen.wikipedia.org%3AVehicle+emissions+control" class="Z3988"></span></span> </li> <li id="cite_note-17"><span class="mw-cite-backlink"><b><a href="#cite_ref-17">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.ecy.wa.gov/programs/air/pdfs/rsd.pdf">"Infrared Remote Sensing Of On-Road Motor Vehicle Emissions In Washington State"</a> <span class="cs1-format">(PDF)</span>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20101231012658/http://www.ecy.wa.gov/programs/air/pdfs/rsd.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 2010-12-31<span class="reference-accessdate">. Retrieved <span class="nowrap">2009-03-23</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Infrared+Remote+Sensing+Of+On-Road+Motor+Vehicle+Emissions+In+Washington+State&rft_id=http%3A%2F%2Fwww.ecy.wa.gov%2Fprograms%2Fair%2Fpdfs%2Frsd.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AVehicle+emissions+control" class="Z3988"></span> <span style="font-size:85%;">(239 KB)</span></span> </li> <li id="cite_note-18"><span class="mw-cite-backlink"><b><a href="#cite_ref-18">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.awel.zh.ch/internet/baudirektion/awel/de/luft_klima_elektrosmog/verkehr/rsd.html">"Abgasmessungen RSD (Measuring pollutants by Remote Sensing in Zurich/Switzerland) by the Kanton's Office for Environmental Protection "awel" by means of equipment provided by Opus Inspection / etest"</a>. <i>www.awel.zh.ch</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20160304192907/http://www.awel.zh.ch/internet/baudirektion/awel/de/luft_klima_elektrosmog/verkehr/rsd.html">Archived</a> from the original on 2016-03-04<span class="reference-accessdate">. Retrieved <span class="nowrap">2016-02-23</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.awel.zh.ch&rft.atitle=Abgasmessungen+RSD+%28Measuring+pollutants+by+Remote+Sensing+in+Zurich%2FSwitzerland%29+by+the+Kanton%27s+Office+for+Environmental+Protection+%22awel%22+by+means+of+equipment+provided+by+Opus+Inspection+%2F+etest.&rft_id=http%3A%2F%2Fwww.awel.zh.ch%2Finternet%2Fbaudirektion%2Fawel%2Fde%2Fluft_klima_elektrosmog%2Fverkehr%2Frsd.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AVehicle+emissions+control" class="Z3988"></span></span> </li> <li id="cite_note-EVOutlook2020-19"><span class="mw-cite-backlink"><b><a href="#cite_ref-EVOutlook2020_19-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFInternational_Energy_Agency_(IEA),_Clean_Energy_Ministerial,_and_Electric_Vehicles_Initiative_(EVI)2020" class="citation web cs1"><a href="/wiki/International_Energy_Agency" title="International Energy Agency">International Energy Agency</a> (IEA), Clean Energy Ministerial, and Electric Vehicles Initiative (EVI) (June 2020). <a rel="nofollow" class="external text" href="https://www.iea.org/reports/global-ev-outlook-2020">"Global EV Outlook 2020: Enterign the decade of electric drive?"</a>. IEA Publications<span class="reference-accessdate">. Retrieved <span class="nowrap">2021-01-10</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Global+EV+Outlook+2020%3A+Enterign+the+decade+of+electric+drive%3F&rft.pub=IEA+Publications&rft.date=2020-06&rft.au=International+Energy+Agency+%28IEA%29%2C+Clean+Energy+Ministerial%2C+and+Electric+Vehicles+Initiative+%28EVI%29&rft_id=https%3A%2F%2Fwww.iea.org%2Freports%2Fglobal-ev-outlook-2020&rfr_id=info%3Asid%2Fen.wikipedia.org%3AVehicle+emissions+control" class="Z3988"></span><span class="cs1-maint citation-comment"><code class="cs1-code">{{<a href="/wiki/Template:Cite_web" title="Template:Cite web">cite web</a>}}</code>: CS1 maint: multiple names: authors list (<a href="/wiki/Category:CS1_maint:_multiple_names:_authors_list" title="Category:CS1 maint: multiple names: authors list">link</a>)</span> <i>See Statistical annex, pp. 247–252 (See Tables A.1 and A.12).</i></span> </li> <li id="cite_note-ChinaNEV2020-20"><span class="mw-cite-backlink"><b><a href="#cite_ref-ChinaNEV2020_20-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFChina_Association_of_Automobile_Manufacturers_(CAAM)2021" class="citation web cs1">China Association of Automobile Manufacturers (CAAM) (2021-01-14). <a rel="nofollow" class="external text" href="http://en.caam.org.cn/Index/show/catid/34/id/140.html">"Sales of New Energy Vehicles in December 2020"</a>. CAAM<span class="reference-accessdate">. Retrieved <span class="nowrap">2021-02-08</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Sales+of+New+Energy+Vehicles+in+December+2020&rft.pub=CAAM&rft.date=2021-01-14&rft.au=China+Association+of+Automobile+Manufacturers+%28CAAM%29&rft_id=http%3A%2F%2Fen.caam.org.cn%2FIndex%2Fshow%2Fcatid%2F34%2Fid%2F140.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AVehicle+emissions+control" class="Z3988"></span> <i>NEV sales in China totaled 1.637 million in 2020, consisting of 1.246 million passenger cars and 121,000 commercial vehicles.</i></span> </li> </ol></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Vehicle_emissions_control&action=edit&section=21" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="http://www.meca.org/">Manufacturers of Emission Controls Association (MECA)</a></li> <li><a rel="nofollow" class="external text" href="http://dieselinformation.aecc.eu">Diesel Information Hub</a></li> <li><a rel="nofollow" class="external text" href="http://www.aecc.eu">Association for Emissions Control by Catalyst (AECC)</a></li> <li><a rel="nofollow" class="external text" href="http://www.familycar.com/CLASSROOM/emission.htm">Emission Control Systems</a> on FamilyCar.com</li> <li><a rel="nofollow" class="external text" href="http://www.epa.gov/nvfel/">National Vehicle and Fuel Emissions Laboratory</a> of the <a href="/wiki/United_States_Environmental_Protection_Agency" title="United States Environmental Protection Agency">United States Environmental Protection Agency</a></li> <li><a rel="nofollow" class="external text" href="https://autocurious.com/vehicle-emissions/">Vehicle emissions and testing</a></li></ul> <div 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engine">Internal combustion engine</a></div></th></tr><tr><td class="navbox-abovebelow" colspan="2"><div><i>Part of the <a href="/wiki/Car" title="Car">Automobile</a> series</i></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Engine_block" title="Engine block">Engine block</a> and<br /> rotating assembly</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Balance_shaft" title="Balance shaft">Balance shaft</a></li> <li><a href="/wiki/Block_heater" title="Block heater">Block heater</a></li> <li><a href="/wiki/Bore_(engine)" title="Bore (engine)">Bore</a></li> <li><a href="/wiki/Connecting_rod" title="Connecting rod">Connecting rod</a></li> <li><a href="/wiki/Crankcase" title="Crankcase">Crankcase</a></li> <li><a href="/wiki/Crankcase_ventilation_system" title="Crankcase ventilation system">Crankcase ventilation system (PCV valve)</a></li> <li><a href="/wiki/Crankpin" title="Crankpin">Crankpin</a></li> <li><a href="/wiki/Crankshaft" title="Crankshaft">Crankshaft</a></li> <li><a href="/wiki/Core_plug" title="Core plug">Core plug (freeze plug)</a></li> <li><a href="/wiki/Cylinder_(engine)" title="Cylinder (engine)">Cylinder</a> (<a href="/wiki/Cylinder_bank" class="mw-redirect" title="Cylinder bank">bank</a>, <a href="/wiki/Engine_configuration" title="Engine configuration">layout</a>)</li> <li><a href="/wiki/Engine_displacement" title="Engine displacement">Displacement</a></li> <li><a href="/wiki/Flywheel" title="Flywheel">Flywheel</a></li> <li><a href="/wiki/Firing_order" title="Firing order">Firing order</a></li> <li><a href="/wiki/Stroke_(engine)" title="Stroke (engine)">Stroke</a></li> <li><a href="/wiki/Main_bearing" title="Main bearing">Main bearing</a></li> <li><a href="/wiki/Piston" title="Piston">Piston</a></li> <li><a href="/wiki/Piston_ring" title="Piston ring">Piston ring</a></li> <li><a href="/wiki/Starter_ring_gear" title="Starter ring gear">Starter ring gear</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Valvetrain" title="Valvetrain">Valvetrain</a> and<br /> <a href="/wiki/Cylinder_head" title="Cylinder head">Cylinder head</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Flathead_engine" title="Flathead engine">Flathead layout</a></li> <li><a href="/wiki/Overhead_camshaft_engine" title="Overhead camshaft engine">Overhead camshaft layout</a></li> <li><a href="/wiki/Overhead_valve_engine" title="Overhead valve engine">Overhead valve (pushrod) layout</a></li></ul> <ul><li><a href="/wiki/Tappet" title="Tappet">Tappet / lifter</a></li> <li><a href="/wiki/Camshaft" title="Camshaft">Camshaft</a></li> <li><a href="/wiki/Chest_(mechanical_engineering)" title="Chest (mechanical engineering)">Chest</a></li> <li><a href="/wiki/Combustion_chamber" title="Combustion chamber">Combustion chamber</a></li> <li><a href="/wiki/Compression_ratio" title="Compression ratio">Compression ratio</a></li> <li><a href="/wiki/Head_gasket" title="Head gasket">Head gasket</a></li> <li><a href="/wiki/Rocker_arm" title="Rocker arm">Rocker arm</a></li> <li><a href="/wiki/Timing_belt_(camshaft)" title="Timing belt (camshaft)">Timing belt</a></li> <li><a href="/wiki/Poppet_valve" title="Poppet valve">Valve</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Forced_induction" title="Forced induction">Forced induction</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Blowoff_valve" title="Blowoff valve">Blowoff valve</a></li> <li><a href="/wiki/Boost_controller" title="Boost controller">Boost controller</a></li> <li><a href="/wiki/Intercooler" title="Intercooler">Intercooler</a></li> <li><a href="/wiki/Supercharger" title="Supercharger">Supercharger</a></li> <li><a href="/wiki/Turbocharger" title="Turbocharger">Turbocharger</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Fuel system</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Diesel_engine" title="Diesel engine">Diesel engine</a></li> <li><a href="/wiki/Petrol_engine" title="Petrol engine">Petrol engine</a></li> <li><a href="/wiki/Carburetor" title="Carburetor">Carburetor</a></li> <li><a href="/wiki/Fuel_filter" title="Fuel filter">Fuel filter</a></li> <li><a href="/wiki/Fuel_injection" title="Fuel injection">Fuel injection</a></li> <li><a href="/wiki/Fuel_pump" title="Fuel pump">Fuel pump</a></li> <li><a href="/wiki/Fuel_tank" title="Fuel tank">Fuel tank</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Ignition_system" title="Ignition system">Ignition</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Ignition_magneto" title="Ignition magneto">Magneto</a></li> <li><a href="/wiki/Compression_ignition" class="mw-redirect" title="Compression ignition">Compression ignition</a></li> <li><a href="/wiki/Coil-on-plug_ignition" class="mw-redirect" title="Coil-on-plug ignition">Coil-on-plug</a></li> <li><a href="/wiki/Distributor" title="Distributor">Distributor</a></li> <li><a href="/wiki/Glow_plug_(diesel_engine)" class="mw-redirect" title="Glow plug (diesel engine)">Glow plug</a></li> <li><a href="/wiki/Ignition_coil" title="Ignition coil">Ignition coil</a></li> <li><a href="/wiki/Spark_plug" title="Spark plug">Spark plug</a></li> <li><a href="/wiki/Spark_plug_wires" title="Spark plug wires">Spark plug wires</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Engine management</div></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Engine_control_unit" title="Engine control unit">Engine control unit (ECU)</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Electrical system</div></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Alternator_(automotive)" title="Alternator (automotive)">Alternator</a></li> <li><a href="/wiki/Automotive_battery" title="Automotive battery">Battery</a></li> <li><a href="/wiki/Dynamo" title="Dynamo">Dynamo</a></li> <li><a href="/wiki/Starter_(engine)" title="Starter (engine)">Starter motor</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Intake system</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Airbox" title="Airbox">Airbox</a></li> <li><a href="/wiki/Air_filter#Internal_combustion_engine_air_filters" title="Air filter">Air filter</a></li> <li><a href="/wiki/Idle_air_control_actuator" title="Idle air control actuator">Idle air control actuator</a></li> <li><a href="/wiki/Inlet_manifold" title="Inlet manifold">Inlet manifold</a></li> <li><a href="/wiki/MAP_sensor" title="MAP sensor">MAP sensor</a></li> <li><a href="/wiki/Mass_flow_sensor" title="Mass flow sensor">MAF sensor</a></li> <li><a href="/wiki/Throttle" title="Throttle">Throttle</a></li> <li><a href="/wiki/Throttle_position_sensor" title="Throttle position sensor">Throttle position sensor</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Exhaust_system" title="Exhaust system">Exhaust system</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Catalytic_converter" title="Catalytic converter">Catalytic converter</a></li> <li><a href="/wiki/Diesel_particulate_filter" title="Diesel particulate filter">Diesel particulate filter</a></li> <li><a href="/wiki/Exhaust_gas_temperature_gauge" title="Exhaust gas temperature gauge">EGT sensor</a></li> <li><a href="/wiki/Exhaust_manifold" title="Exhaust manifold">Exhaust manifold</a></li> <li><a href="/wiki/Muffler" title="Muffler">Muffler</a></li> <li><a href="/wiki/Oxygen_sensor#Automotive_applications" title="Oxygen sensor">Oxygen sensor</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Internal_combustion_engine_cooling" title="Internal combustion engine cooling">Cooling system</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Air_cooling" title="Air cooling">Air cooling</a></li> <li><a href="/wiki/Water_cooling" title="Water cooling">Water cooling</a></li></ul> <ul><li><a href="/wiki/Fan_(machine)" title="Fan (machine)">Electric fan</a></li> <li><a href="/wiki/Radiator_(engine_cooling)" title="Radiator (engine cooling)">Radiator</a></li> <li><a href="/wiki/Thermostat" title="Thermostat">Thermostat</a></li> <li><a href="/wiki/Fan_clutch" title="Fan clutch">Viscous fan (fan clutch)</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Lubrication</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Motor_oil" title="Motor oil">Oil</a></li> <li><a href="/wiki/Oil_filter" title="Oil filter">Oil filter</a></li> <li><a href="/wiki/Oil_pump_(internal_combustion_engine)" title="Oil pump (internal combustion engine)">Oil pump</a></li> <li><a href="/wiki/Sump" title="Sump">Sump</a> (<a href="/wiki/Wet_sump" title="Wet sump">Wet sump</a>, <a href="/wiki/Dry_sump" title="Dry sump">Dry sump</a>)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Other</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Engine_knocking" title="Engine knocking">Knocking / pinging</a></li> <li><a href="/wiki/Power_band" title="Power band">Power band</a></li> <li><a href="/wiki/Redline" title="Redline">Redline</a></li> <li><a href="/wiki/Stratified_charge_engine" title="Stratified charge engine">Stratified charge</a></li> <li><a href="/wiki/Dead_centre_(engineering)" title="Dead centre (engineering)">Top dead centre</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow hlist" colspan="2" 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