Symptoms of a Bad or Failing Fuel Injector

Fuel injectors are an engine management component that is found on the vast majority of road going vehicles. They are a part of the vehicle’s fuel system and act as the nozzles that spray the fuel into the engine. They are controlled by the engine computer and operate by spraying the fuel in specific patterns and at specific timed intervals that will optimize engine performance. They are found on the vast majority of road going vehicles in one form or another. Because they are a part of the fuel system, any problems with the fuel injectors can cause all sorts of engine performance issues, that can sometimes even render the vehicle undrivable. Usually a bad or failing fuel injector will produce a few symptoms that can alert the driver of a potential issue

1. Engine misfires and decrease in power, acceleration, and fuel efficiency

One of the most common symptoms of a potential problem with a fuel injector is engine performance issues. If any of the vehicle’s fuel injectors have an issue, the air fuel ratio of the engine will be upset, which can result in performance problems. A faulty fuel injector can cause the vehicle to experience misfires, a loss in power and acceleration, a reduction in fuel efficiency, and in severe cases can cause stalling or prevent the engine from running at all.

2. Fuel odor

Another common symptom of a potential issue with a fuel injector is a fuel smell. Injectors hold high pressures which over time can cause them to leak at the nozzle or at the seal that is located at the tip of the injector. A leaky injector will excess fuel into the combustion chamber of the engine, while a leaky seal will leak fuel at the base of the injector. Both can affect engine performance, specifically fuel efficiency, and both will usually produce a noticeable fuel smell. Any sort of fuel smells should be addressed as soon as possible in order to prevent them from becoming a potential safety hazard.

3. Check Engine Light comes on

Another symptom of a potential issue with a fuel injector is an illuminated Check Engine Light. If any of the fuel injectors become clogged and cause a misfire, or experience an electrical issue the computer will set off the Check Engine Light to alert the driver of the issue. The Check Engine Light can also be activated by a wide variety of other engine management issues, so having the computer scanned for trouble codes is highly recommended.

Because of their role as the nozzles that provide the fuel that allows the engine to run, fuel injectors are a very important component to the overall operation and drivability of the vehicle. If your vehicle is displaying any of the symptoms above, or you suspect that your vehicle may be having an issue with one of the fuel injectors, have the vehicle diagnosed by a professional technician, such as one from YourMechanic, to determine if any of the fuel injectors need to be replaced.


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Raymond

37 years of experience
402 reviews
Raymond
37 years of experience
Chevrolet Impala V6-3.4L - Fuel System - Las Vegas, Nevada
Raymond was very knowledgeable mechanic and through in his testing. I trust him for any future from your mechanic.
Acura TL - Car is overheating Inspection - Las Vegas, Nevada
He always goes above and beyond and honestly seems like a great guy. Probably the best mechanic I've ever had.

Torrieanto

12 years of experience
632 reviews
Torrieanto
12 years of experience
Volkswagen Tiguan L4-2.0L Turbo - Check Engine Light is on - Brandon, Florida
Good service, punctual and very professional I recommend the service
Volkswagen * - Pre-purchase Car Inspection - Tampa, Florida
Torrieanto was absolutely fantastic in helping me to evaluate a 1974 Volkswagen bus I am purchasing from a seller on eBay. He checked out every tiny aspect of the vehicle and provided me a full report back on both the good and the bad of the car. I would absolutely hire him again. Thank you, Torrieanto!!

Johnny

33 years of experience
264 reviews
Johnny
33 years of experience
Toyota Corolla L4-1.6L - Fuel System Inspection - Sacramento, California
Johnny did a great job

Arturo

27 years of experience
303 reviews
Arturo
27 years of experience
Nissan Titan V8-5.6L - Fuel System Inspection - La Mesa, California
Informative and efficient

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