Misfire Causes and Solutions

Updated on January 22, 2019
Benjimester profile image

I've worked in a variety of hands-on professions and love to write about topics that can save readers from needless expenses.

What Is Misfiring?

What is misfiring and what are the causes of misfiring? In order to understand that, let's talk a little bit first about the internal combustion engine.

The best way to think about an internal combustion engine is to think of a bicycle. Every time a cyclist pushes down on the pedal, the bike gets another small burst of power. It's the same with an internal combustion engine. A bicycle is like a 2-cylinder engine, and every time the cyclist pushes down on the pedal, the bike fires. A misfire occurs when one of the cylinders in an internal combustion engine doesn't fire. Think again of the bike. If a cyclist was only able to use one leg to power the bike, he could still move it and ride it. But it wouldn't have very much power. It's the same with engine misfiring. When a cylinder in an internal combustion engine misfires, the engine can still function, it just doesn't have as much power as it otherwise would. In order for a cylinder to fire properly in an internal combustion engine, it needs 4 factors all working together in concert:

  • Proper Fuel/Air Mixture
  • Proper Compression
  • Proper Timing
  • Correct Spark

Misfire causes are often simple, like a fouled spark plug that can no longer fire.
Misfire causes are often simple, like a fouled spark plug that can no longer fire.

Misfire Causes

If one or more of the above factors aren't in proper working condition, you'll run the risk of misfiring. There are a variety of different misfire causes that can occur that can keep a cylinder from combusting properly. Sometimes it takes a combination of issues in order to make a cylinder misfire. Other times, misfiring isn't consistent, and sometimes the cylinder will fire properly, while other times the cylinder will misfire. It depends on the type of issue and how severe the issues are.

  1. Faulty or Fouled Spark Plugs: Spark plugs provide the spark for the ignition of the fuel/air mixture in the combustion chamber. But spark plugs can go bad for a number of reasons and are one of the leading causes of misfiring. Spark plugs can get fouled from oil leaking into the combustion chamber, or from carbon buildup. They can also wear down more quickly from overheating and improper gapping. The bottom line is that if you're experiencing misfiring, one of the leading causes is bad spark plugs. It's easy to check and easy to fix. Even if you don't want to do the job yourself, most oil change operations will check and replace your spark plugs for you during an oil change for less than $100. Repairing the cause of your misfiring can save you that much money pretty quick in the boosted fuel economy you'll experience.
  2. Cracked Distributor Cap: The distributor is what controls the timing of the spark that gets sent in sequence to each of the spark plugs in the engine. This has to do with the timing mentioned in the list above. When the distributor is functioning properly, the spark to each spark plug is sent at just the right time to ignite the fuel/air mixture right when the piston is ready. A cracked or damaged distributor cap can cause the signal to be lost to one or more of the spark plugs, resulting in a misfire.
  3. Lean Fuel/Air Mixture: The fuel/air mixture is a pretty delicate balance. If the mixture gets out of balance, it can cause a misfire. So what are some ways that the fuel/air mixture can get out of balance? If things like the fuel pump or the fuel injectors get clogged, then not enough fuel will be able to get to the combustion chamber and can readily cause a misfire. This problem can lead to consistent misfiring in all cylinders, and not be restricted to just one.
  4. Lack of Compression: When the piston fires and is pushed down by the combustion, the piston is then pushed back up again as more fuel/air mixture is brought into the combustion chamber. This upward motion is called compression. If a cylinder lacks proper compression, then the spark from the spark plug won't ignite the fuel/air mixture. Lack of compression can be caused by a variety of things, but mostly by leaky exhaust valve that's been burned, or else a blown head gasket. In either case, you've got a pretty major problem. One way to tell whether your head gasket is causing the problems or a leaky exhaust valve is to see if two cylinders next to each other are misfiring. If so, then you most likely are dealing with a blown head gasket instead of a leaky exhaust valve. In addition to this, if an engine overheats or runs hot, and if you're noticing that you're also mysteriously losing coolant, then you most likely are dealing with a blown head gasket.

Fixing Misfiring

Now that you understand the causes of misfiring, the best thing you can do would be to take your car to your mechanic or local auto parts store and have them hook the car up to a diagnostic machine to read the misfire codes and tell you the nature of your misfire. If your misfire is localized to just one cylinder, it will tell you which cylinder. At that point, you can check your distributor cap to make sure it's intact and check the spark plug in that cylinder. You can also check the compression of that cylinder using the same diagnostic tool to analyze whether or not the exhaust valve in that cylinder is leaking or perhaps whether or not you have a blown head gasket.

If the misfire codes tell you that multiple cylinders are misfiring intermittently, then you can start to surmise that perhaps your fuel/air mixture is too lean and is causing misfiring in different cylinders at different times. If that's the case, then you might want to think about cleaning your fuel injectors with fuel injection cleaner and perhaps changing your fuel pump. If that isn't the problem either and you're experiencing consistent misfiring in all cylinders, at that point, you'll want to take a look at your timing as a whole to make sure that everything is set to fire at the proper times.

This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.

© 2012 Benji Mester


    0 of 8192 characters used
    Post Comment
    • profile image


      12 months ago

      my Honda can't raised at all pls what is the fault

    • profile image

      lucy ogbonnaya 

      13 months ago

      This is a very helpful website, very thorough explanations and easy to understand. My car engine Renault Clio 16V 1.4 is shaking alot and jerking whenever Iam reverse parking or going on a hilly road. My driving is no longer smooth. I have an appointment at the garage where they suggested to change the spark plugs, fingers crossed it will sort out the problem. Will give feedback;-)

    • profile image


      15 months ago

      Just a suggestion to inspect the spark plug and verify that the center electrode is not making contact with the side electrode as they need to have a small gap in between. This cause my 250 cc dirt bike to misfire after i changed the spark plug. If so you can lift the side electrode with a pliers.

    • profile image

      Adnan ferozi 

      19 months ago

      Ninja 300 spark plug conditions is very good . but during ride misfire continue all gears........

    • profile image


      2 years ago

      piaggio MP3 500cc single cylinder with 2 spark plugs. New plugs were fitted and misfire started. Fires on 1 plug not 2. checked if both spark outside engine, and both sparked on earth contact. Never before did I have this problem. HELP PLEASE

    • profile image


      3 years ago

      I like the way you deal with questions


    This website uses cookies

    As a user in the EEA, your approval is needed on a few things. To provide a better website experience, axleaddict.com uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

    For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at: https://maven.io/company/pages/privacy

    Show Details
    HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
    LoginThis is necessary to sign in to the HubPages Service.
    Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
    AkismetThis is used to detect comment spam. (Privacy Policy)
    HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
    HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
    Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
    CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
    Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the googleapis.com or gstatic.com domains, for performance and efficiency reasons. (Privacy Policy)
    Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
    Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
    Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
    Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
    Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
    VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
    PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
    Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
    MavenThis supports the Maven widget and search functionality. (Privacy Policy)
    Google AdSenseThis is an ad network. (Privacy Policy)
    Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
    Index ExchangeThis is an ad network. (Privacy Policy)
    SovrnThis is an ad network. (Privacy Policy)
    Facebook AdsThis is an ad network. (Privacy Policy)
    Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
    AppNexusThis is an ad network. (Privacy Policy)
    OpenxThis is an ad network. (Privacy Policy)
    Rubicon ProjectThis is an ad network. (Privacy Policy)
    TripleLiftThis is an ad network. (Privacy Policy)
    Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
    Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
    Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
    Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
    ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
    Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)
    ClickscoThis is a data management platform studying reader behavior (Privacy Policy)