My engine is misfiring: What are the causes & symptoms?


Posted by: Jane Osuagwu

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The engine is the heart of the car and needs to be in good condition for optimum performance. An engine misfire should be fixed immediately. Check out the causes and symptoms

Are you having a hard time dealing with an engine misfire? Probably you're thinking that it's a worse issue and so will cost much to fix. Engine misfire often shows different symptoms and this depends on the engine's make and model. Whether the symptoms are as a result of the model or make, the aftereffect is the same-a short delay in the delivery of power. This problem can be for a shorter time or it will keep happening. However, if you take action without any delay, you won't spend much fixing it. As pieced on Naijauto, this article will let you know the causes and symptoms of an engine misfire.

Let's see some of the causes of an engine misfire

Causes of engine misfire

A car engine uses three elements to ensure the cylinder fires properly. They are the proper quantity of fuel, oxygen that will burn the fuel and heat to spark off an ignition. The inadequacy of any of them or even their absence will result in an engine misfire.

Other reasons for an engine misfire are:

  • Incorrect ignition timing
  • Vacuum leaks
  • Worn out valve spring


A car engine uses fuel, oxygen, and heat to ensure the cylinder fires properly

Symptoms of engine misfire

1. Ignition system

The ignition parts which include ignition wires, spark plugs and coil parks can corrode or wear out over time. Each has a lifespan that has been set for it so when that time elapses, they’ll need to be replaced. When any of these mentioned parts start wearing out, there'll be a time when the spark plug will no longer receive enough electricity to elicit a spark. It will start by giving off irregular misfires and with time, will become worse. You don't have to get worked up by the repair as the parts found in the ignition system aren't expensive.

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2. Damaged cylinder wall

When an engine misfires, it will start producing sneezing or popping sounds. On some occasions, it will also give off a distinct smell which is a blend of coolant, steam, and gasoline. The strong smell is a telltale sign that the cylinder walls have damaged. Visit the mechanic as soon as possible to examine the engine.


When the engine starts giving off a distinct smell, know that the cylinder walls have damaged

3. Components in the fuel system

The parts found inside the fuel system can also be responsible for the engine misfire though they wear out slowly. Check the fuel filter to know if it has clogged. The fuel injector should be inspected for dirt and not forgetting the mass airflow sensor too. If the EGR valve hasn't been cleaned up for a long time, it could stick. As a result, the exhaust fumes will be allowed inside the intake manifold where it will cause an engine misfire. To fix these problems, clean the parts or replace the problematic ones.

Now, you might want to know if it's safe to keep driving your car when the engine misfires. Here’s the answer.

Is it safe to keep driving your car when the engine misfires?

There's no danger lurking around when you drive with an engine misfire. However, when it lingers on, it will get worse. When you don't fix the engine misfire issue immediately, it will end up damaging your engine parts like the oxygen sensor and catalytic converter. You might want to consider your safety when the car stops on a busy road. Again, engine misfire will increase your car's emission and reduce fuel efficiency.


If you don't fix the engine misfire immediately, it will ruin the oxygen sensor

When an engine misfire happens, visit the auto repair shop immediately. This is going to help increase the lifespan of your engine and make sure you're safe while driving.

>>> Check out our tips and advice section for more car care techniques!

Jane Osuagwu

Jane Osuagwu

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Jane Osuagwu is an automotive writer at She's a car enthusiast who loves creating educative and informative topics on cars, ranging from maintenance tips to updates on the latest trend in the auto industry in concise and friendly writing. 

Jane is also a blogger and loves reading, inspiring people and getting involved in personal development projects.

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