If a fuel injector is dirty i.e. the injector is clogged, the fuel spraying into the engine is going to be restricted. if the fuel injector is dirty you are going to face problems while starting and going WOT
Sometimes, it may happen that the external electrical connectors of the fuel injector may get corroded or may even break. This is the symptom of a weak or intermittent firing.
If you have a leaky fuel injector, that is probably because the injector pintle is not sitting on the orifice perfectly. This may cause difficulties in starting the car and in some cases may cause damage to the oxygen sensors.
Sometimes, the fuel additives remain unburnt and settle on the injector pintle. This may alter flow volume and fuel spraying pattern. This too will result in poor engine performance, a sluggish pickup and oxygen sensor damage. In some cases, it may also result in leaking of the fuel injector and engine overheating.
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