{"id":12250,"date":"2021-10-29T01:28:00","date_gmt":"2021-10-29T08:28:00","guid":{"rendered":"https:\/\/blogv2prod.wpenginepowered.com\/blog\/?p=12250"},"modified":"2026-02-10T01:25:09","modified_gmt":"2026-02-10T09:25:09","slug":"p0304-code-cylinder-4-misfire-detected","status":"publish","type":"post","link":"https:\/\/www.carparts.com\/blog\/p0304-code-cylinder-4-misfire-detected\/","title":{"rendered":"P0304 Code: Cylinder 4 Misfire Detected"},"content":{"rendered":"<!DOCTYPE html PUBLIC \"-\/\/W3C\/\/DTD HTML 4.0 Transitional\/\/EN\" \"http:\/\/www.w3.org\/TR\/REC-html40\/loose.dtd\">\n<html><body><span class=\"span-reading-time rt-reading-time\" style=\"display: block;\"><span class=\"rt-label rt-prefix\">Reading Time: <\/span> <span class=\"rt-time\"> 5<\/span> <span class=\"rt-label rt-postfix\">minutes<\/span><\/span><style>.kadence-column12250_eeba84-44 > .kt-inside-inner-col{border-top-width:0px;border-right-width:0px;border-bottom-width:0px;border-left-width:0px;}.kadence-column12250_eeba84-44 > .kt-inside-inner-col,.kadence-column12250_eeba84-44 > .kt-inside-inner-col:before{border-top-left-radius:0px;border-top-right-radius:0px;border-bottom-right-radius:0px;border-bottom-left-radius:0px;}.kadence-column12250_eeba84-44 > .kt-inside-inner-col{column-gap:var(--global-kb-gap-sm, 1rem);}.kadence-column12250_eeba84-44 > .kt-inside-inner-col{flex-direction:column;}.kadence-column12250_eeba84-44 > .kt-inside-inner-col > .aligncenter{width:100%;}.kadence-column12250_eeba84-44 > .kt-inside-inner-col:before{opacity:0.3;}.kadence-column12250_eeba84-44{position:relative;}@media all and (max-width: 1024px){.kadence-column12250_eeba84-44 > .kt-inside-inner-col{flex-direction:column;justify-content:center;}}@media all and (max-width: 767px){.kadence-column12250_eeba84-44 > .kt-inside-inner-col{flex-direction:column;justify-content:center;}}<\/style>\n<div class=\"wp-block-kadence-column kadence-column12250_eeba84-44 inner-column-1 qk-look-widget\"><div class=\"kt-inside-inner-col\">\n<div class=\"wp-block-ultimate-post-row ultp-block-0e38e0  qk-main-wrap\"><div class=\"ultp-row-wrapper\"><div class=\"ultp-row-content\">\n<div class=\"wp-block-ultimate-post-column ultp-block-58028b\"><div class=\"ultp-column-wrapper\"><style>.wp-block-kadence-advancedheading.kt-adv-heading12250_c44409-dd, .wp-block-kadence-advancedheading.kt-adv-heading12250_c44409-dd[data-kb-block=\"kb-adv-heading12250_c44409-dd\"]{text-align:center;font-size:20px;font-style:normal;}.wp-block-kadence-advancedheading.kt-adv-heading12250_c44409-dd mark.kt-highlight, .wp-block-kadence-advancedheading.kt-adv-heading12250_c44409-dd[data-kb-block=\"kb-adv-heading12250_c44409-dd\"] mark.kt-highlight{font-family:Inter;font-weight:500;font-style:normal;color:#f76a0c;-webkit-box-decoration-break:clone;box-decoration-break:clone;padding-top:0px;padding-right:0px;padding-bottom:0px;padding-left:0px;}.wp-block-kadence-advancedheading.kt-adv-heading12250_c44409-dd img.kb-inline-image, .wp-block-kadence-advancedheading.kt-adv-heading12250_c44409-dd[data-kb-block=\"kb-adv-heading12250_c44409-dd\"] img.kb-inline-image{width:150px;vertical-align:baseline;}<\/style>\n<div class=\"kt-adv-heading12250_c44409-dd summary-title wp-block-kadence-advancedheading\" data-kb-block=\"kb-adv-heading12250_c44409-dd\"><span>Summary<\/span><\/div>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The P0304 code stands for &ldquo;Cylinder 4 Misfire Detected&rdquo;, which means your vehicle&rsquo;s cylinder 4 has misfired enough times for your powertrain control module (PCM) to notice.<\/li>\n\n\n\n<li>A worn spark plug, a faulty fuel injector, and a leaking valve are some possible causes of the P0304 code.<\/li>\n\n\n\n<li>Some common symptoms of the P0304 code are an illuminated check engine light, rough idling, and excessive fuel consumption.<\/li>\n<\/ul>\n<\/div><\/div>\n<\/div><\/div><\/div>\n<\/div><\/div>\n\n\n\n\n\n<p>The P0304 engine code can compromise your driving experience, so resolve the underlying cause (or causes) immediately. If your check engine light is on and the <a href=\"https:\/\/www.carparts.com\/blog\/search-obd2-codes-list\/\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"OBD-II\">OBD-II<\/a> scanner reads a P0304 code, use the guide below to address it.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">What Does the P0304 Code Mean?<\/h2>\n\n\n\n<p>Diagnostic trouble code (DTC) P0304 stands for &ldquo;Cylinder 4 Misfire Detected.&rdquo; The code indicates that <strong>the powertrain control module (PCM) has counted enough misfire events on cylinder 4 to store the misfire code for that cylinder.<\/strong> Cylinder refers to the fourth cylinder as the cylinders are numbered.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"683\" src=\"https:\/\/www.carparts.com\/blog\/wp-content\/uploads\/2020\/07\/checking-cylinder-head-1024x683.jpeg\" alt=\"checking cylinder head\" class=\"wp-image-12267\" style=\"width:1024px;height:683px\" srcset=\"https:\/\/www.carparts.com\/blog\/wp-content\/uploads\/2020\/07\/checking-cylinder-head-1024x683.jpeg 1024w, https:\/\/www.carparts.com\/blog\/wp-content\/uploads\/2020\/07\/checking-cylinder-head-300x200.jpeg 300w, https:\/\/www.carparts.com\/blog\/wp-content\/uploads\/2020\/07\/checking-cylinder-head-768x512.jpeg 768w, https:\/\/www.carparts.com\/blog\/wp-content\/uploads\/2020\/07\/checking-cylinder-head-600x400.jpeg 600w, https:\/\/www.carparts.com\/blog\/wp-content\/uploads\/2020\/07\/checking-cylinder-head.jpeg 1500w\" sizes=\"(max-width: 1024px) 100vw, 1024px\"><figcaption class=\"wp-element-caption\">Code P0304 indicates that the powertrain control module (PCM), has counted enough misfire events on cylinder 4 to store the misfire code for that cylinder.<\/figcaption><\/figure>\n\n\n\n<p>Jump to the next section to quickly learn the most likely causes of code  P0304. To learn more about firing order, read our explanation <a href=\"https:\/\/www.carparts.com\/blog\/error-code-p0301-cylinder-1-misfire-detected\/#Cylinder_Number_1_Location_and_Firing_Order\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"here\">here<\/a>. For an in-depth discussion of how the engine computer knows which cylinder is misfiring, you can read more <a href=\"https:\/\/www.carparts.com\/blog\/p0300-code-random-or-multiple-cylinder-misfire-detected\/#An_In-Depth_Look_at_Cylinder_Misfires\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"here\">here<\/a>.<\/p>\n\n\n\n<p>Finally, for more information on how misfires happen, you can check out our technical  explanation <a href=\"https:\/\/www.carparts.com\/blog\/error-code-p0301-cylinder-1-misfire-detected\/#How_a_Misfire_Happens\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"here\">here<\/a>.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">P0304 on Some Ford Vehicles<\/h3>\n\n\n\n<p>The code appears in a 2009 Ford F-150 FX4 5.4L V8 because of the following conditions:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Air leaks in the Air Induction system (e.g., in the intake manifold)<\/li>\n\n\n\n<li>Fuel delivery problem (e.g., a contaminated, dirty or sticking fuel injector)<\/li>\n\n\n\n<li>Driving the vehicle low on fuel (less than 1\/8 of a tank)<\/li>\n\n\n\n<li>Base engine mechanical problem that affects only Cylinder 4<\/li>\n\n\n\n<li>Air leaks in the EGR system and in its related hoses and\/or valve<\/li>\n\n\n\n<li>Air leaks in the PCV system and in its related hoses and\/or valve<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">What are the Possible Causes of the P0304 Code?<\/h2>\n\n\n\n<p>There are a lot of components in your car&rsquo;s <a href=\"https:\/\/www.carparts.com\/blog\/car-engine-parts\/\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"engine\">engine<\/a> and each one could prove to be the root cause of the trouble code. However, due to the trouble code being specific to cylinder 4, you can eliminate some areas and components that work irrespective of its functions.&nbsp;<\/p>\n\n\n\n<div id=\"article-search-widget\">\n<div class=\"cp-search\">\n<div align=\"center\">\n<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/cld.partsimg.com\/image\/upload\/w_auto,dpr_auto\/carparts\/logos\/badge_wordmark\/full_color\/CP_LOGO_COLOUR_RGB\" alt=\"CarParts.com\" width=\"300\" height=\"56\">\n<\/div>\n<form id=\"cpsearchform\" name=\"cpsearchform\" action=\"https:\/\/www.carparts.com\/search\" method=\"get\" target=\"_blank\" accept-charset=\"character_set\" aria-label=\"search CarParts.com\">\n    <input type=\"text\" class=\"keyword\" name=\"q\" placeholder=\"Search for parts on CarParts.com\" value=\"\" aria-label=\"Search CarParts.com\"><input type=\"submit\" class=\"btn-search\" value=\"Search\" aria-label=\"Search\">\n<\/form>\n<\/div>\n<\/div>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Ignition system problems, such as:\n<ul class=\"wp-block-list\">\n<li>A faulty worn spark plug<\/li>\n\n\n\n<li>A failed coil pack or coil-on-plug coil<\/li>\n\n\n\n<li>A bad spark plug wire on a vehicle that has plug wires<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>Fuel delivery issues, such as:\n<ul class=\"wp-block-list\">\n<li>A faulty fuel injector<\/li>\n\n\n\n<li>Wiring issues with the fuel injector circuit (e.g., loose connections, damaged wires)<\/li>\n\n\n\n<li>Problems with the powertrain control module, such as a damaged injector driver<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li>Engine mechanical problems, such as:\n<ul class=\"wp-block-list\">\n<li>A leaking valve<\/li>\n\n\n\n<li> A worn piston ring, a damaged piston or damaged cylinder walls<\/li>\n\n\n\n<li>A worn camshaft lobe or <a href=\"https:\/\/www.carparts.com\/blog\/bad-lifter-symptoms-noise-replacement-cost-and-more\/\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"damaged lifter\">damaged lifter<\/a><\/li>\n\n\n\n<li>A leaking head gasket<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image size-large is-resized\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"681\" src=\"https:\/\/www.carparts.com\/blog\/wp-content\/uploads\/2021\/06\/mechanic-holding-a-dirty-and-worn-spark-plug-1024x681.jpg\" alt=\"mechanic holding a dirty and worn spark plug\" class=\"wp-image-39732\" style=\"width:1024px;height:681px\" srcset=\"https:\/\/www.carparts.com\/blog\/wp-content\/uploads\/2021\/06\/mechanic-holding-a-dirty-and-worn-spark-plug-1024x681.jpg 1024w, https:\/\/www.carparts.com\/blog\/wp-content\/uploads\/2021\/06\/mechanic-holding-a-dirty-and-worn-spark-plug-300x199.jpg 300w, https:\/\/www.carparts.com\/blog\/wp-content\/uploads\/2021\/06\/mechanic-holding-a-dirty-and-worn-spark-plug-768x510.jpg 768w, https:\/\/www.carparts.com\/blog\/wp-content\/uploads\/2021\/06\/mechanic-holding-a-dirty-and-worn-spark-plug-600x400.jpg 600w, https:\/\/www.carparts.com\/blog\/wp-content\/uploads\/2021\/06\/mechanic-holding-a-dirty-and-worn-spark-plug-150x100.jpg 150w, https:\/\/www.carparts.com\/blog\/wp-content\/uploads\/2021\/06\/mechanic-holding-a-dirty-and-worn-spark-plug.jpg 1500w\" sizes=\"(max-width: 1024px) 100vw, 1024px\"><figcaption class=\"wp-element-caption\">A faulty worn spark plug can cause the P0304 code.<\/figcaption><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">What are the Common Symptoms of the P0304 Code?<\/h2>\n\n\n\n<p>How can you tell if you&rsquo;re dealing with a P0304? Even before you use an OBD-II scanner to check for trouble codes, there are a number of signs you can keep an eye out for that can alert you to the possibility of a P0304 or any similar error codes.<\/p>\n\n\n\n<p>There are several P304 engine misfire symptoms to look out for. Below are some of them:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><a href=\"https:\/\/www.carparts.com\/blog\/check-engine-light-flashing\/\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"Check engine light is turned on\">Check engine light is turned on<\/a><\/li>\n\n\n\n<li>Difficulty in starting the engine<\/li>\n\n\n\n<li>Stalling<\/li>\n\n\n\n<li>Rough engine idling<\/li>\n\n\n\n<li>Diminished power, especially when driving uphill<\/li>\n\n\n\n<li>Excessive fuel consumption<\/li>\n\n\n\n<li>Exhaust emits a foul odor<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">How to Diagnose the P0304 Code<\/h2>\n\n\n\n<p>P0304 must not be ignored. All potential causes must be looked into to come up with the correct diagnosis. Consider taking your vehicle to a professional automotive technician if you don&rsquo;t have enough DIY auto repair experience and skills. However, if you still want to take a stab at the diagnosis process, the videos below can help you do it correctly.<\/p>\n\n\n\n<figure class=\"wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n<iframe loading=\"lazy\" title=\"Misfire Quick Tests (Is it a spark, fuel or compression problem?)\" width=\"500\" height=\"281\" src=\"https:\/\/www.youtube.com\/embed\/uB9XCDO8oa8?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe>\n<\/div><\/figure>\n\n\n\n<figure class=\"wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n<iframe loading=\"lazy\" title=\"How to repair car engine error failure code P0302\" width=\"500\" height=\"281\" src=\"https:\/\/www.youtube.com\/embed\/CJHek_s0dZs?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe>\n<\/div><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">How to Fix the P0304 Code<\/h2>\n\n\n\n<p>When it comes to OBD-II trouble codes, there is no such thing as a &ldquo;magic bullet&rdquo; solution. The repair process can vary depending on the root cause of the code, or even the vehicle&rsquo;s make and model. <\/p>\n\n\n\n<p>For example, some of the most common documented fixes for a P0304 code on a 2008 <a href=\"https:\/\/www.carparts.com\/ford\/f-150\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"Ford F-150\">Ford F-150<\/a> XL 4.2L involved replacing either an ignition coil, a <a href=\"https:\/\/www.carparts.com\/blog\/bad-spark-plug-symptoms\/\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"spark plug\">spark plug<\/a>, or a <a href=\"https:\/\/www.carparts.com\/blog\/the-top-6-signs-of-bad-fuel-injectors\/\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"fuel injector\">fuel injector<\/a>. Meanwhile, the most common P0304 repair for certain Dodge vehicles, such as a 2014 <a href=\"https:\/\/www.carparts.com\/dodge\/durango\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"Dodge Durango\">Dodge Durango<\/a>, Limited 3.6L, involved replacing the offending cylinder.<\/p>\n\n\n\n<p>If you&rsquo;re not confident with your automotive know-how, it may be best to leave the task to an expert. However, if you are certain of your DIY skills, identify the underlying issue that triggered the P0304 code. Then, consult <a href=\"https:\/\/www.carparts.com\/blog\/best-online-resources-to-help-you-learn-how-to-fix-cars\/\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"online auto repair resources\">online auto repair resources<\/a> and guides to figure out the right solution to the problem. <\/p>\n\n\n\n<p>You can also invest in an ALLDATA single-vehicle subscription, which can help you solve other automotive issues that you may encounter in the future. <\/p>\n\n\n\n<p>Make sure to check your owner&rsquo;s manual before attempting to fix a code P0304.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">How To Get Quality Replacement Parts To Fix the P0304 Code<\/h2>\n\n\n\n<p>Whatever&rsquo;s causing your vehicle to throw a P0304 code is likely to cause even more damage down the line. In some cases, you might even find it hard to start the engine, leaving you stranded. Avoid the worst-case scenario by identifying the culprit and replacing it as soon as possible. Thankfully, you can easily order quality replacement parts at CarParts.com.&nbsp;<\/p>\n\n\n\n<p>Whether your vehicle&rsquo;s P0304 code is caused by a faulty fuel injector, a leaking valve, or bad spark plugs, you&rsquo;re sure to find a part that fits your vehicle from our wide selection of products. Plus, you can expect to receive your new component in as fast as two business days, thanks to our strategically located warehouses around the US.&nbsp;<\/p>\n\n\n\n<p>Don&rsquo;t wait until the worst-case scenario happens before fixing your P0304 code. Check out our <a href=\"https:\/\/www.carparts.com\/spark-plug\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"spark plugs\">spark plugs<\/a>, <a href=\"https:\/\/www.carparts.com\/fuel-injector\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"fuel injectors\">fuel injectors<\/a>, and other replacement parts at CarParts.com today.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Products Mentioned in this Guide<\/h2>\n\n\n\n<div class=\"reusable-productlink\">\n\n<!-- start of editable content -->\n\n<a href=\"https:\/\/www.carparts.com\/spark-plug\" target=\"_blank\" aria-label=\"Spark Plug\" rel=\"noopener\">\n<img decoding=\"async\" src=\"https:\/\/cld.partsimg.com\/image\/upload\/d_noimage.jpg,h_200,w_200,c_pad,f_auto,q_auto,dpr_auto,e_sharpen\/images\/ng2164_1\">\n<strong>Spark Plug<\/strong>\n<\/a>\n\n<a href=\"https:\/\/www.carparts.com\/spark-plug-wire\" target=\"_blank\" aria-label=\"Spark Plug Wire\" rel=\"noopener\">\n<img decoding=\"async\" src=\"https:\/\/cld.partsimg.com\/image\/upload\/d_noimage.jpg,h_200,w_200,c_pad,f_auto,q_auto,dpr_auto,e_sharpen\/images\/reps504801_1\">\n<strong>Spark Plug Wire<\/strong>\n<\/a>\n\n<a href=\"https:\/\/www.carparts.com\/piston-ring-set\" target=\"_blank\" aria-label=\"Piston Ring Set\" rel=\"noopener\">\n<img decoding=\"async\" src=\"https:\/\/cld.partsimg.com\/image\/upload\/d_noimage.jpg,h_200,w_200,c_pad,f_auto,q_auto,dpr_auto,e_sharpen\/images\/rf38140001_1\">\n<strong>Piston Ring Set<\/strong>\n<\/a>\n\n<a href=\"https:\/\/www.carparts.com\/head-gasket-set\" target=\"_blank\" aria-label=\"Head Gasket Set\" rel=\"noopener\">\n<img decoding=\"async\" src=\"https:\/\/cld.partsimg.com\/image\/upload\/d_noimage.jpg,h_200,w_200,c_pad,f_auto,q_auto,dpr_auto,e_sharpen\/images\/repc312508_1\">\n<strong>Head Gasket Set<\/strong>\n<\/a>\n\n<!-- end of editable content -->\n\n<\/div>\n\n\n\n<div class=\"shop-project\">\n\n    <h2>Shop this Project<\/h2>\n\n    <ul class=\"shop-project-list\">\n        \n        <li>\n            <div class=\"shop-project-item\">\n                <div class=\"stp-image-url\">\n                    <a href=\"https:\/\/www.carparts.com\/details\/intake-manifold\/replacement\/rf31190001\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label='&lt;img src=\"https:\/\/cld.partsimg.com\/image\/upload\/images\/rf31190001_1\" alt=\"Replacement &ndash; Intake Manifold, Black, Plastic, Includes Thermostat and Seal, PCV Connector and O-Ring, Auxiliary Coolant Fitting, 8 Small and 14 Large Screws\" \/&gt;'><img decoding=\"async\" src=\"https:\/\/cld.partsimg.com\/image\/upload\/images\/rf31190001_1\" alt=\"Replacement &ndash; Intake Manifold, Black, Plastic, Includes Thermostat and Seal, PCV Connector and O-Ring, Auxiliary Coolant Fitting, 8 Small and 14 Large Screws\"><\/a>\n                <\/div>\n\n                <div class=\"stp-desc\">\n                                            <p class=\"stp-title\">\n                            <a href=\"https:\/\/www.carparts.com\/details\/intake-manifold\/replacement\/rf31190001\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"Replacement &ndash; Intake Manifold, Black, Plastic, Includes Thermostat and Seal, PCV Connector and O-Ring, Auxiliary Coolant Fitting, 8 Small and 14 Large Screws\">Replacement &ndash; Intake Manifold, Black, Plastic, Includes Thermostat and Seal, PCV Connector and O-Ring, Auxiliary Coolant Fitting, 8 Small and 14 Large Screws<\/a>\n                        <\/p>\n                    \n                    <div class=\"stp-stars\">\n                        <img decoding=\"async\" src=\"https:\/\/cld.partsimg.com\/image\/upload\/q_auto,dpr_auto,f_auto\/carparts\/blog\/widgets\/shop-project\/stars\/star-4.5.svg\" alt=\"4.5 Stars\">\n                    <\/div>\n\n                                            <p class=\"stp-price\">$184.99<\/p>\n                    \n                    <p><small>Price and rating may change from the time content is published.<\/small><\/p>\n\n                                            <p class=\"stp-cta\">\n                            <a href=\"https:\/\/www.carparts.com\/details\/intake-manifold\/replacement\/rf31190001\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"Shop Now\">Shop Now<\/a>\n                        <\/p>\n                                    <\/div>\n\n            <\/div>\n        <\/li>\n\n        \n        <li>\n            <div class=\"shop-project-item\">\n                <div class=\"stp-image-url\">\n                    <a href=\"https:\/\/www.carparts.com\/details\/fuel-injector\/replacement\/repf314302\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label='&lt;img src=\"https:\/\/cld.partsimg.com\/image\/upload\/images\/repf314302_1\" alt=\"Replacement &ndash; Fuel Injector - Sold Individually, New\" \/&gt;'><img decoding=\"async\" src=\"https:\/\/cld.partsimg.com\/image\/upload\/images\/repf314302_1\" alt=\"Replacement &ndash; Fuel Injector - Sold Individually, New\"><\/a>\n                <\/div>\n\n                <div class=\"stp-desc\">\n                                            <p class=\"stp-title\">\n                            <a href=\"https:\/\/www.carparts.com\/details\/fuel-injector\/replacement\/repf314302\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"Replacement &ndash; Fuel Injector &ndash; Sold Individually, New\">Replacement &ndash; Fuel Injector &ndash; Sold Individually, New<\/a>\n                        <\/p>\n                    \n                    <div class=\"stp-stars\">\n                        <img decoding=\"async\" src=\"https:\/\/cld.partsimg.com\/image\/upload\/q_auto,dpr_auto,f_auto\/carparts\/blog\/widgets\/shop-project\/stars\/star-4.5.svg\" alt=\"4.5 Stars\">\n                    <\/div>\n\n                                            <p class=\"stp-price\">$22.99<\/p>\n                    \n                    <p><small>Price and rating may change from the time content is published.<\/small><\/p>\n\n                                            <p class=\"stp-cta\">\n                            <a href=\"https:\/\/www.carparts.com\/details\/fuel-injector\/replacement\/repf314302\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"Shop Now\">Shop Now<\/a>\n                        <\/p>\n                                    <\/div>\n\n            <\/div>\n        <\/li>\n\n        \n        <li>\n            <div class=\"shop-project-item\">\n                <div class=\"stp-image-url\">\n                    <a href=\"https:\/\/www.carparts.com\/details\/Dodge\/Grand_Caravan\/A-Premium\/Ignition_Coil\/2004\/PRMIC0067.html\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label='&lt;img src=\"https:\/\/cld.partsimg.com\/images\/prmic0067_1\" alt=\"A-Premium&reg; &ndash; 2004 Dodge Grand Caravan - Ignition Coil, Naturally Aspirated, GAS, Mini Passenger Van, Sold Individually, 3.8L 6Cyl\" \/&gt;'><img decoding=\"async\" src=\"https:\/\/cld.partsimg.com\/images\/prmic0067_1\" alt=\"A-Premium&reg; &ndash; 2004 Dodge Grand Caravan - Ignition Coil, Naturally Aspirated, GAS, Mini Passenger Van, Sold Individually, 3.8L 6Cyl\"><\/a>\n                <\/div>\n\n                <div class=\"stp-desc\">\n                                            <p class=\"stp-title\">\n                            <a href=\"https:\/\/www.carparts.com\/details\/Dodge\/Grand_Caravan\/A-Premium\/Ignition_Coil\/2004\/PRMIC0067.html\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"A-Premium&reg; &ndash; 2004 Dodge Grand Caravan &ndash; Ignition Coil, Naturally Aspirated, GAS, Mini Passenger Van, Sold Individually, 3.8L 6Cyl\">A-Premium&reg; &ndash; 2004 Dodge Grand Caravan &ndash; Ignition Coil, Naturally Aspirated, GAS, Mini Passenger Van, Sold Individually, 3.8L 6Cyl<\/a>\n                        <\/p>\n                    \n                    <div class=\"stp-stars\">\n                        <img decoding=\"async\" src=\"https:\/\/cld.partsimg.com\/image\/upload\/q_auto,dpr_auto,f_auto\/carparts\/blog\/widgets\/shop-project\/stars\/star-4.5.svg\" alt=\"4.5 Stars\">\n                    <\/div>\n\n                                            <p class=\"stp-price\">$45.99<\/p>\n                    \n                    <p><small>Price and rating may change from the time content is published.<\/small><\/p>\n\n                                            <p class=\"stp-cta\">\n                            <a href=\"https:\/\/www.carparts.com\/details\/Dodge\/Grand_Caravan\/A-Premium\/Ignition_Coil\/2004\/PRMIC0067.html\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"Shop Now\">Shop Now<\/a>\n                        <\/p>\n                                    <\/div>\n\n            <\/div>\n        <\/li>\n\n        \n        <li>\n            <div class=\"shop-project-item\">\n                <div class=\"stp-image-url\">\n                    <a href=\"https:\/\/www.carparts.com\/details\/valve-lifter\/replacement\/repd321701\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label='&lt;img src=\"https:\/\/cld.partsimg.com\/images\/repd321701_2\" alt=\"Replacement&reg; &ndash; Rear Valve Lifter, 5.7L\/6.4L Hemi Engines\" \/&gt;'><img decoding=\"async\" src=\"https:\/\/cld.partsimg.com\/images\/repd321701_2\" alt=\"Replacement&reg; &ndash; Rear Valve Lifter, 5.7L\/6.4L Hemi Engines\"><\/a>\n                <\/div>\n\n                <div class=\"stp-desc\">\n                                            <p class=\"stp-title\">\n                            <a href=\"https:\/\/www.carparts.com\/details\/valve-lifter\/replacement\/repd321701\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"Replacement&reg; &ndash; Rear Valve Lifter, 5.7L\/6.4L Hemi Engines\">Replacement&reg; &ndash; Rear Valve Lifter, 5.7L\/6.4L Hemi Engines<\/a>\n                        <\/p>\n                    \n                    <div class=\"stp-stars\">\n                        <img decoding=\"async\" src=\"https:\/\/cld.partsimg.com\/image\/upload\/q_auto,dpr_auto,f_auto\/carparts\/blog\/widgets\/shop-project\/stars\/star-3.5.svg\" alt=\"3.5 Stars\">\n                    <\/div>\n\n                                            <p class=\"stp-price\">$85.99<\/p>\n                    \n                    <p><small>Price and rating may change from the time content is published.<\/small><\/p>\n\n                                            <p class=\"stp-cta\">\n                            <a href=\"https:\/\/www.carparts.com\/details\/valve-lifter\/replacement\/repd321701\" target=\"_blank\" rel=\"noreferrer noopener\" aria-label=\"Shop Now\">Shop Now<\/a>\n                        <\/p>\n                                    <\/div>\n\n            <\/div>\n        <\/li>\n\n            <\/ul>\n<\/div>\n\n\n<\/body><\/html>\n","protected":false},"excerpt":{"rendered":"<p><span class=\"span-reading-time rt-reading-time\" style=\"display: block;\"><span class=\"rt-label rt-prefix\">Reading Time: <\/span> <span class=\"rt-time\"> 5<\/span> <span class=\"rt-label rt-postfix\">minutes<\/span><\/span>The P0304 engine code can compromise your driving experience, so resolve the underlying cause (or causes) immediately. If your check&#8230; <a href=\"https:\/\/www.carparts.com\/blog\/p0304-code-cylinder-4-misfire-detected\/\" rel=\"nofollow\">Read More<\/a><\/p>\n","protected":false},"author":1651,"featured_media":12266,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_genesis_hide_title":false,"_genesis_hide_breadcrumbs":false,"_genesis_hide_singular_image":false,"_genesis_hide_footer_widgets":false,"_genesis_custom_body_class":"","_genesis_custom_post_class":"","_genesis_layout":"","footnotes":""},"categories":[1314],"tags":[3354],"ppma_author":[2607,2985],"class_list":{"0":"post-12250","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-obd-ii-trouble-codes","8":"tag-car-engine-all-articles","9":"entry"},"acf":{"adrotate_specific_mobile_ad":"","adrotate_specific_desktop_ad":""},"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.6 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>P0304 Code: Cylinder 4 Misfire Detected - In The Garage with CarParts.com<\/title>\n<meta name=\"description\" content=\"The P0304 code indicates a misfire in cylinder 4. 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