Q: I had #3 fuel injector to go out in my car. It was replaced and within a week the light came back on with same problem.

Hi, thanks for writing in. If it is only the #3 injector both times, more than likely there is a short in the engine wiring harness or possible the PCM. First thought was that maybe there is a lot of debris in the bottom of the fuel tank possibly clogging injectors, but if it only #3, then it’s probably electrical. I would recommend having an expert from YourMechanic come to your home or office to confirm a diagnosis on the electrical issue and make or suggest the necessary repairs or replacements.