My engine was recently misfiring and I replaced all of the spark plugs as a first attempt to get things working. It did not fix the problem, and the misfire continued. However, I did notice that for the 4th cylinder of my car, the spark plug gap was significantly increased and it looked as though the tip had been worn away. This was maybe expected given the plugs had never been replaced and the car was about 60k miles, but all other spark plugs looked to be in good condition.

I later identified through a service that it was the 4th cylinder coil pack that was faulty. It was replaced, but now I am concerned that running the car with the faulty coil pack may have damaged the new spark plug in the 4th cylinder.

Should I be concerned? The engine seems to be running fine.

1 Answer 1


No. There should be absolutely no reason for concern. Even if it was an old plug, I wouldn't be worried. If the coil isn't firing, it means there's no electricity being passed. The plug is just ... well ... sitting there. It might have a bit of residual fuel on it from not being used when the coil wasn't firing, but this should burn off during the next heating cycle. Again, no reason to fret. Nothing to see. Move along. :o)


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