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Home> How To> Repair Injector > Symptoms of Bad Fuel Injectors

Symptoms of Bad Fuel Injectors


Fuel Injector


The fuel injector controls the flow of fuel into the engine cylinder and is the last stop before the fuel combusts. Basically, it is an electrically operated gate that injects the perfect amount of fuel to run the engine. We recommend that you clean your injectors every 25,000 to 30,000 miles to ensure that they do not get clogged. However, sometimes they do go bad, and below are some of the symptoms of a bad fuel injector.


Rough Engine Idle

One of the most common symptoms of faulty fuel injectors is an extremely violent or rough engine when the car is sitting in idle. If fuel is not properly provided to the engine cylinder, a choppy engine while sitting in idle will occur.


Gasoline Leak


Fuel injector can crack or break, which will cause a gas leak. Any cracks on the exterior body of the injector can cause fuel to leak from the body rather than the flowing through the nozzle. If a damaged injector is the cause of the leak, the gasoline will both be visible on the injector and cause a smell.  Be sure to check the fuel rails for leaks as well.


Poor Fuel Economy


Naturally, if there is a gasoline leak due to a faulty injector, the direct result would be poor fuel economy. A faulty injector may also inject too much gasoline into the engine, wasting gasoline and lowering fuel economy.


Surging Engine


When too much gasoline is injected into your engine, it causes the engine to surge too fast and then accelerate too slowly. When driving, this will feel like the car will leap up but have a hard time taking off.


Misfiring Engine


A misfiring engine is the effect of the opposite problem – the fuel injector is not injecting enough fuel into the engine. This symptom is caused by clogged injectors, so make sure your injectors are clean. When driving, this will feel like the vehicle is not responding or is delayed when you try to accelerate. This symptom will require immediate response since a misfire could give rise to engine overheating and pre-igniting the fuel mixture.




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