Can You Drive a Car With a Bad Fuel Injector?


Fuel injectors are an integral part of your engine, without them, your car will simply not drive. But what if your fuel injectors are dirty? stuck? leaking? or have generally gone bad? Can you still drive?

In this article, we’ll discuss the prerequisites you need to know to answer that question. As well as provide additional information on everything about it.

Can You Drive a Car With a Bad Fuel Injector?

Not recommended but it depends. 

-If your fuel injectors are dirty, meaning they can still deliver fuel in a gaseous form but are insufficient for the engine, the car will only misfire.

– If your fuel injectors are stuck and won’t open to deliver fuel into the intake tract, the car would not even start in the first place.

– If your fuel injectors are leaking meaning they drip fuel in liquid form and not in gaseous form, that is very dangerous and you should restraint from driving until the problem is solved. Otherwise, this could cause a hydrostatic lock where the piston could break, connecting rods could bend or break, valves also could break or bend. Especially in an interference type of engine.

– If your fuel injector is stuck on the nozzle due to a bad control, this also could cause a hydrostatic lock, as the nozzles would dump more fuel than necessary, and the system would be flooded and spark plugs will become dirty.

By the symptoms we listed above, you can probably tell that it will be quite destructive for your engine in some cases, it’s much easier and cheaper to replace a fuel injector than a whole engine. If despite all of that you still chose to drive, be ready to accept the following consequences:

  • Burnt Pistons.
  • Piston Damage.
  • Jerks When Driving.
  • Black Smoke From Exhaust.
  • Hydrostatic Lock.
  • Connecting Rods Could Bend Or Break.
  • Valves Also Could Break Or Bend.
  • The System Could Flood 
  • Spark Plugs Will Become Dirty Leading To a Malfunction.

Related: Why is My Car With Automatic Transmission Jerking?

How To Tell If Your Fuel Injector Is Bad?

You might already know if you googled “Can you drive a car with a bad fuel injector?” but in case you didn’t know, here are the symptoms of a bad fuel injector.

The following symptoms are the most common symptoms of faulty fuel injectors:

  • Jerks when driving
  • Bad acceleration
  • The engine vibrates when switching gears, or when decelerating.
  • Increased Fuel Consumption
  • As a result of irregular fuel consumption, black smoke may be coming out of the exhaust pipe on diesel engines.

If you notice any of the problems above, make sure to check the fuel injectors as soon as possible. Otherwise, the car may fail in the most unpleasant situation.

What Causes a Fuel Injector To Fail

As debris (water, soil particles, etc.) or rust gets into the system, fuel injectors will start to go bad, and, after time, it may plug up the nozzle, the armature, or the nozzle needle gets stuck.

We recommend doing whatever you can to keep your fuel system clean in order to prevent debris from getting into the system.

The biggest reason for fuel injector failure is low-grade fuel. If your faulty fuel injectors are left for too long it can cause serious engine damage that can require major repair

How To Check The Fuel Injector

First of all, there are many types of injectors (mechanical and electromagnetic) and their design has significant differences, which means that their testing methods should also differ.

We will show you the most popular methods. You don’t need to remove the injectors to find out how to check that the injectors are working properly.

This method is one of the simplest checks and involves checking by sound (or analyzing the noise made by the engine during operation).

Usually, clogged or damaged injectors emit a muffled high-frequency noise (the sound usually comes from the cylinder block). But there are also other ways to check your fuel injector:

Checking By Ear And a Screwdriver

  • Start your engine
  • Take the longest screwdriver and put it in the base of the fuel injector.
  • Put your ear to the handle of the screwdriver and listen carefully to the sound.
  • Be careful! When checking the injectors with this method, your clothes, hair, etc. should not hang over the parts!


If while listening to the fuel injector you hear a continuous series of clicks of even and not very loud, it can be assumed that the injector is working properly.


If the clicks are intermittent, irregular, and with pauses, the injector is likely to jam and requires flushing or even replacement. This injector should be removed for further diagnosis.

The described procedure should be performed for each injector, after which you decide whether it makes sense to visit the service station or not.

This method does not give 100% certainty, but a preliminary conclusion can be made. In addition, it is free and available to everyone. If there are problems with the injectors, this method, will at least, help to make sure that the problem is really there.

After such a diagnosis, you can try to restore the nozzle by flushing, or go to the mechanic shop and make a full cleaning of the nozzles on the ultrasound stand.


We hope we provided enough information to help you understand whenever you can drive with a bad fuel injector. Always make sure to take care of your injectors, use good fuel, keep your fuel system clean, avoid corrosion, etc.

If your faulty fuel injectors are left for too long it can cause serious engine damage that can require major repair

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