BY BENJAMIN JEREW / ORIGINALLY PUBLISHED MARCH 8, 2018 / NATIONAL AUTOMOTIVE PARTS ASSOCIATION / As a driver, there’s no greater frustration than seeing your check&hellip;{"id":10429,"date":"2018-04-23T10:19:01","date_gmt":"2018-04-23T17:19:01","guid":{"rendered":"http:\/\/www.pomonaswapmeet.com\/blog\/?p=10429"},"modified":"2018-04-23T10:19:01","modified_gmt":"2018-04-23T17:19:01","slug":"check-engine-light","status":"publish","type":"post","link":"https:\/\/www.pomonaswapmeet.com\/blog\/2018\/04\/23\/check-engine-light\/","title":{"rendered":"Is Your Check Engine Light On? Here Are 5 Common Culprits"},"content":{"rendered":"<h5><span style=\"color: #000000;\">BY BENJAMIN JEREW \/ ORIGINALLY PUBLISHED MARCH 8, 2018 \/\u00a0NATIONAL AUTOMOTIVE PARTS ASSOCIATION \/<\/span><\/h5>\n<p><span style=\"color: #000000;\">As a driver, there\u2019s no greater frustration than seeing your check engine light on for no obvious reason \u2014 or after you\u2019ve already repaired what you thought was the issue. The real problem is that the check engine light is so ambiguous.<\/span><\/p>\n<p><span style=\"color: #000000;\">With the check engine light on, it\u2019s important to note that there are some 5,000 diagnostic trouble codes (DTCs) that might be behind it. Fortunately, some DTCs are more common, and usually easier to diagnose, than others. Here are five of the most common problems that can illuminate your check engine light, along with their DTCs, which are useful if you attempt to access your on-board diagnostics system.<\/span><\/p>\n<h3><span style=\"color: #000000;\"><strong>1. Faulty Oxygen Sensor<\/strong><\/span><\/h3>\n<p><span style=\"color: #000000;\">Oxygen sensors monitor fuel trim and catalytic converter functioning, depending on location. Uncorrected fuel trim, due to a faulty oxygen sensor or heating circuit, results in higher emissions, lower fuel economy and possible damage to the catalytic converter.<\/span><\/p>\n<p><span style=\"color: #000000;\">The common DTCs are P0030, P0131 and P0165.<\/span><\/p>\n<h3><span style=\"color: #000000;\"><strong>2. Faulty Ignition<\/strong><\/span><\/h3>\n<p><span style=\"color: #000000;\">Ignition coils, spark plug wires and spark plugs are designed to deliver a precisely timed spark to burn fuel in the cylinder, but damage or weakness can lead to incomplete combustion or a misfire. A faulty ignition should be remedied immediately.<\/span><\/p>\n<p><span style=\"color: #000000;\">The common DTCs are P030x and P035x.<\/span><\/p>\n<h3><span style=\"color: #000000;\"><strong>3. Failed Catalytic Converter<\/strong><\/span><\/h3>\n<p><span style=\"color: #000000;\">The catalytic converter reduces emissions from harmful compounds found in car exhaust by converting them into less harmful compounds before they leave the exhaust system. However, overheating, underheating or contamination can reduce its effectiveness and lead to your check engine light illuminating.<\/span><\/p>\n<p><span style=\"color: #000000;\">The common DTC for this issue is P0420.<\/span><\/p>\n<h3><span style=\"color: #000000;\"><strong>4. EVAP Problems<\/strong><\/span><\/h3>\n<p><span style=\"color: #000000;\">To keep unburned fuel vapors from contaminating the atmosphere, a system of tubes, valves and a charcoal canister store them until they can be burned in the engine. This is called the evaporative emission control, or EVAP, system. Faulty valves are common, but refueling while the engine is running or forgetting to install the<\/span>\u00a0<strong><a class=\"SWhtmlLink\" href=\"https:\/\/www.napaonline.com\/en\/p\/BK_7031780?cid=social_blog_022018_Gas_Cap\" target=\"_blank\" rel=\"noopener noreferrer\">gas cap<\/a><\/strong>\u00a0<span style=\"color: #000000;\">are more common, all of which can trigger the check engine light.<\/span><\/p>\n<p><span style=\"color: #000000;\">The common DTCs related to the EVAP system are P0440, P0446 and P0455.<\/span><\/p>\n<h3><span style=\"color: #000000;\"><strong>5. Contaminated MAF<\/strong><\/span><\/h3>\n<p><span style=\"color: #000000;\">The mass air flow (MAF) sensor samples and measures air going into the intake system, but blockage or contamination can skew sensor readings, leading to fuel trim problems. Cleaning it might help, but sometimes the vehicle requires a replacement sensor for a sure fix.<\/span><\/p>\n<p><span style=\"color: #000000;\">The common DTCs related to the MAF sensor are P0171 and P0172.<\/span><\/p>\n<p><span style=\"color: #000000;\">Thanks to advanced electronic controls, today\u2019s engines are more powerful, cleaner and more efficient than ever before, but everything wears out, burns out or breaks eventually. Delaying check-engine-light repairs can lead to reduced fuel economy and even collateral damage. For example, the check engine light might be on due to a spark plug or thermostat issue, but ignoring it could result in catalytic converter failure.<\/span><\/p>\n<p><span style=\"color: #000000;\">Even if your vehicle seems to be operating well for the moment, it\u2019s important to resolve small issues when your check engine light comes on to avert bigger problems. There\u2019s\u00a0<\/span><strong><a class=\"SWhtmlLink\" href=\"http:\/\/knowhow.napaonline.com\/check-engine-light-turned-whats-next\/\" target=\"_blank\" rel=\"noopener noreferrer\">no need to panic<\/a><\/strong><span style=\"color: #000000;\">, but have your vehicle scanned, diagnosed and repaired as soon as possible.<\/span><\/p>\n<p><span style=\"color: #000000;\">Check out all the\u00a0<\/span><strong><a href=\"https:\/\/www.napaonline.com\/en\/c\/tools-equipment\" target=\"_blank\" rel=\"noopener noreferrer\">tools &amp; equipment<\/a><\/strong>\u00a0<wbr \/><span style=\"color: #000000;\">available on<\/span>\u00a0<strong><a title=\"Click to open in a new window or tab https:\/\/www.napaonline.com\/\" href=\"https:\/\/www.napaonline.com\/\" target=\"_blank\" rel=\"noopener noreferrer\">NAPA Online<\/a><\/strong>\u00a0<span style=\"color: #000000;\">or trust one of their 16,000<\/span>\u00a0<a title=\"Click to open in a new window or tab http:\/\/www.napaautocare.com\/store-finder.aspx\" href=\"http:\/\/www.napaautocare.com\/store-finder.aspx\" target=\"_blank\" rel=\"noopener noreferrer\"><strong>NAPA AutoCare locations<\/strong><\/a>\u00a0<span style=\"color: #000000;\">for routine maintenance and repairs. For more information about check engine light problems, chat with a knowledgeable expert at your<\/span> <a title=\"Click to open in a new window or tab https:\/\/www.napaonline.com\/en\/store-locator\" href=\"https:\/\/www.napaonline.com\/en\/store-locator\" target=\"_blank\" rel=\"noopener noreferrer\"><strong>local NAPA AUTO PARTS store<\/strong><\/a><span style=\"color: #000000;\">.<\/span><\/p>\n<p><span style=\"color: #000000;\">Photo Credit: <\/span><a href=\"https:\/\/www.flickr.com\/photos\/isherwoodchris\/9460454176\/\" target=\"_blank\" rel=\"noopener\"><strong>On [46 of 52]<\/strong><\/a> <span style=\"color: #000000;\">by<\/span> <a href=\"https:\/\/www.flickr.com\/photos\/isherwoodchris\/\" target=\"_blank\" rel=\"noopener\"><strong>Chris Isherwood<\/strong><\/a> <span style=\"color: #000000;\">(<\/span><a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/2.0\/legalcode\" target=\"_blank\" rel=\"noopener\"><strong>CC BY-SA 2.0<\/strong><\/a><span style=\"color: #000000;\">)<\/span><\/p>\n<p><i><span style=\"color: #000000;\">This article has been reproduced with the permission of the copyright holder, National Automotive Parts Association. Further reproduction is prohibited without permission. Click here for more<\/span>\u00a0<\/i><strong><i><a href=\"http:\/\/knowhow.napaonline.com\/\" target=\"_blank\" rel=\"noopener noreferrer\">automotive tips and stories<\/a><\/i><\/strong><i>\u00a0<span style=\"color: #000000;\">from NAPA, or here for more information on<\/span>\u00a0<strong><a href=\"http:\/\/www.pomonaswapmeet.com\/event-info\/car-show-hours-dates\/\" target=\"_blank\" rel=\"noopener noreferrer\">the next Pomona Swap Meet &amp; Classic Car Show<\/a><\/strong><span style=\"color: #000000;\">.<\/span><\/i><\/p>\n","protected":false},"excerpt":{"rendered":null,"protected":false},"author":98,"featured_media":10430,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"cos_headline_score":0,"cos_seo_score":0,"cos_headline_text":"","cos_headline_has_been_analyzed":false,"cos_last_analyzed_headline":[],"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[805],"tags":[5764,3056,6235,3475,4259,6232,6239,6245,6244,6241,6242,6243,6237,6236,6234,6258,4827,3032,6257,6240,6238,3491,3037,3026,6233,6246,6249,6250,6255,6256,6247,6248,6251,6252,6253,6254,3053,3029],"aioseo_notices":[],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/www.pomonaswapmeet.com\/blog\/wp-content\/uploads\/2018\/04\/Check-Engine-Light.jpg?fit=3264%2C2448&ssl=1","jetpack_shortlink":"https:\/\/wp.me\/p9nnZN-2Id","jetpack_sharing_enabled":true,"jetpack_likes_enabled":true,"_links":{"self":[{"href":"https:\/\/www.pomonaswapmeet.com\/blog\/wp-json\/wp\/v2\/posts\/10429"}],"collection":[{"href":"https:\/\/www.pomonaswapmeet.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.pomonaswapmeet.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.pomonaswapmeet.com\/blog\/wp-json\/wp\/v2\/users\/98"}],"replies":[{"embeddable":true,"href":"https:\/\/www.pomonaswapmeet.com\/blog\/wp-json\/wp\/v2\/comments?post=10429"}],"version-history":[{"count":2,"href":"https:\/\/www.pomonaswapmeet.com\/blog\/wp-json\/wp\/v2\/posts\/10429\/revisions"}],"predecessor-version":[{"id":10432,"href":"https:\/\/www.pomonaswapmeet.com\/blog\/wp-json\/wp\/v2\/posts\/10429\/revisions\/10432"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.pomonaswapmeet.com\/blog\/wp-json\/wp\/v2\/media\/10430"}],"wp:attachment":[{"href":"https:\/\/www.pomonaswapmeet.com\/blog\/wp-json\/wp\/v2\/media?parent=10429"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.pomonaswapmeet.com\/blog\/wp-json\/wp\/v2\/categories?post=10429"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.pomonaswapmeet.com\/blog\/wp-json\/wp\/v2\/tags?post=10429"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}