Engine Misfire: Causes, Signs, and How to Fix It

When your car sputters, jerks, or loses power suddenly, you’re likely dealing with an engine misfire, a condition where one or more cylinders fail to ignite fuel properly. Also known as a cylinder misfire, it’s not just a nuisance—it’s a warning that something in your ignition, fuel, or air system is failing. This isn’t something you can ignore. Left unchecked, an engine misfire can damage your catalytic converter, wreck your spark plugs, or even cause your engine to seize.

Most misfires happen because of three things: bad spark plugs, the tiny but critical components that ignite the air-fuel mix in each cylinder, a failing fuel pump, the part that delivers gasoline to the engine under pressure, or a clogged air filter, which restricts airflow and throws off the fuel mixture. These aren’t abstract problems—they’re common failures you can diagnose yourself. If your car hesitates when you press the gas, or the check engine light flashes, those are red flags. You might hear a rhythmic popping sound from the exhaust, or feel the whole car shake at idle. These aren’t normal. They mean combustion isn’t happening right.

It’s easy to blame the fuel pump when your car won’t start, but misfires often start with something simpler. A worn spark plug can lose its spark after 30,000 miles. A dirty air filter can cut airflow by 20%—enough to throw off the whole engine. And if your fuel pump is weak, it won’t deliver enough pressure, even if it’s still running. You don’t need a diagnostic tool to spot these issues. Listen. Feel. Look. The signs are there. The posts below show you exactly what to check, how to test each part, and which replacements actually work. No guesswork. No overpriced repairs. Just clear, step-by-step fixes for the most common causes of engine misfire.