Fuel injector is the main part of the Audi A4 fuel injection system. There has to be a good working fuel injector for the proper delivery of fuel into the engine. Thus, its defectiveness will certainly affect the performance of Audi A4 a lot. Failure of the O-ring, cracks on the nozzle, leak - will cause a fuel injector to go bad. Here in the video, you can get a brief idea about the signs of a bad fuel injector. Please have a look & take measures accordingly.
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