(Updated on April 19, 2021)
When a car has a misfire, it means that internal combustion in the cylinder did not finish completely. The car will still be able to run and you’ll be able to drive it, but you’ll start to notice the engine jerking a lot.
This could be followed by exhaust smoke coming out of the tailpipe, the smell of gas, and loud popping sounds. When you experience these symptoms, you likely have an engine misfire (aka cylinder misfire).
You’ll want to get your vehicle examined by a mechanic right away if your home mechanic skills aren’t up to par yet. If you let the symptoms above go for too long, it could end up damaging your engine.
What Does an Engine Misfire Feel Like?
An engine misfire will be recognizable to the driver because their engine will feel like its stumbling for a few seconds and then regain its pace again. The number of times this happens will depend on the seriousness of the misfire.
If at least one spark plug is not firing correctly then it will cause the engine to malfunction and run terribly. The car may still move, but you will notice an increase in your vehicle’s exhaust emissions, a lack of acceleration and a reduction in the engine’s power.
If you step on the gas pedal and it takes awhile for your car to go faster while leaving behind a cloud of smoke behind you, this probably means you have a misfire.
At this point, your engine will require more fuel than necessary just to operate at its normal level. This will result in you having to spend more money on gas.
What Does an Engine Misfire Sound Like?
The best way to describe the noise a cylinder misfire makes is to think of popcorn kernels randomly popping. In some vehicles it can also sound like a “chug” or sneeze. While a backfire is technically different than a misfire, a loud “bang” or “poot” can be heard from both.
Top 5 Reasons Your Car Misfires
There are lots of reasons as to why a car would misfire in the first place. To help you understand what might have been the cause of your car misfire, below are five of the most common causes that someone could experience in this situation.
1) Air to Fuel Ratio Imbalance
One of the main reasons for an engine misfire can be attributed to an imbalance in the air to fuel ratio within the internal combustion chamber. This usually means there is not enough fuel and too much air being mixed together.
For the combustion to be successful, the mixture needs a specific proportion of fuel for the amount of air entering the engine. Otherwise, you will notice the cylinder misfire while your engine is idling. But when you’re driving at faster speeds, the symptoms of the misfire will go away.
2) Ignition System Issues
There could be a problem coming from any one of the components in the ignition system. Perhaps the spark plugs aren’t creating an adequate spark for the internal combustion chamber.
You could also have a worn-out ignition coil, ignition cables, rotor, or distributor cap. If any of these problems exist, the internal combustion chamber’s air and fuel mixture won’t be able to ignite properly.
The weak spark will cause an engine misfire, but you might not notice right away. But as you operate the vehicle, you’ll feel its jerkiness very well.
3) Transmission Issues
There are times when the misfire might not even come from your engine. It could come from the transmission instead. If your car starts to jerk around like an engine misfire had occurred, your transmission may not be able to adequately shift up or down.
You will notice this more when you’re driving at faster speeds. This is a bad situation like any other misfire and you need to have it repaired right away.
4) Mechanical Problems
Your vehicle is made up of many mechanical parts which contribute to the functionality of the engine. There are piston rings, camshaft lobes, valves, and cylinder walls.
If any of these parts were to get worn out, it could cause an engine misfire. The same goes for when there’s an intake manifold gasket leak or a head gasket leak.
Other possible mechanical issues may include a bad fuel injector or damaged rocker arms. Check the timing belt to see if that’s installed correctly too because it may have slipped.
You will know when there’s a misfire caused by mechanical issues because there will be a thumping feeling from the vehicle that will never go away, regardless of your speed.
5) ECM Problems
Sometimes there may be a glitch in the engine control module or the central computer of the vehicle which manages the engine. Any minor glitch there could throw off the combustion process and cause a misfire.
Fortunately, there is an easy remedy to this type of problem that works most of the time. If you simply disconnect your battery for a few minutes and then reconnect it. It’s similar to rebooting a computer at home and this should solve any minor glitch or bug in the computer system.
If the bug still exists after that, then you need to have the central computer examined at the dealership where you got the car.