WP_DEBUG Signs of a clogged fuel injector. 9 best indicators - GARAGE BEAST

Signs of a clogged fuel injector. 9 best indicators

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Is your car taking time to start, or you feel lag or jerks while driving? Chances are that these are the signs of a clogged fuel injector.

Most of the time it’s because you have missed your injector maintenance schedule, mostly it is around 30,000 miles but you should also check your car manual.

These injectors are clogged due to carbon deposits that are in gas or diesel. Overtime these small deposits stick on to your injector and creates difficulty in longer for your car.

The best option is to get them cleaned from a professional mechanic and they can check if it was only, the carbon deposits or there are cracks on the injector too.

Below we have shown an infographic and also explained the symptoms that can help you identify if your injectors are clogged or not.

This infographic shows the signs of a clogged fuel injector.

Hard start or no start

If your car is Either taking time to start or not starting at all chances are that this is Signs of a clogged fuel injector are clogged and the injectors are not letting your car start properly.

Get your car checked your nearest workshop or if it doesn’t start at all you can try to do mild cleaning if injectors yourself if you can which will let the car drive for some more time and get to your nearest garage.

Acceleration delay

The second sign of a clogged injectors is that your car does not respond to the acceleration it used to do and you feel that there is a delay when you press the accelerator pedal and the picking up the acceleration.

Stalling engine

Third sign of a clogged fuel injector is that your car stalls while driving. This sign is the one you should take seriously as this issue may leave you stranded on the road, you also may feel that your vehicle vibrates when its idle.

It’s because the injectors are clogged and the engine is not getting the fuel that it requires to operate and that is the reason the Engine is stalling.

Check engine Light

If you have newer car chances are that it may give you a check engine light warning you to get the car checked.

If the car is showing other signs mentioned here than chances are that the check engine light is because of that too.


When you are driving your car accelerating the car or leave accelerator and you hear crackling sound from exhaust or the car feel like misfiring this might be one of the signs of a clogged fuel injector.

This is because of your car not getting the accurate amount of fuel and it’s the job of injector to accurately send the correct amount of fuel.

Engine Performance issues

Are you feeling that the car performance is deteriorated overtime and it doesn’t feel like it used to be in the past, then you might need to get your vehicle inspected.

In this case it is not compulsory that your injectors are clogged but there can be other issues such as throttle body, spark plugs or some electrical issues.

Fuel economy gets worse

Another reason after your injectors getting clogged is that your car will give less mileage.

Newer cars have the speedometers that show the MPG so when you see that your car mileage has dropped from what it usually used to give then get your vehicle inspected.

Your car is getting less fuel than needed and that is why it is showing less mileage, chances are that mileage drops because of other issues so its better to get it checked.

Poor Emission

A clogged fuel injector causes the car to have poor Emission and can cause further problems for you if you keep on running it with bad fuel injectors.

If your car has poor emissions then your car will also most likely fail to pass the yearly inspection. So, its better to get your car checked in this case before your car fails the inspection.

Signs of a poor emission can be bad smell from your car exhaust or car struggling to accelerate in this case you might have a choked catalytic convertor.

Dancing RPM

The last sign in this list is if you see that either your car is on idle or while driving and the RPM needle continues to go up and down the speedometer. This might be one of Signs of a clogged fuel injector.

The RPM needle keeps on dancing is because your car is struggling to get the fuel it needs and increases the RPM in the reaction to get more fuel.