I need help! Here's the scoop.
Saturday...car running fine. Get new spark-plugs (motorcarft awsf-32pp) gap them at .050 and install. Now car has a stumble/miss/hesitation at part throttle between 1000rpm and 3000rpm. Not at the same rpm every time, and not all the time. Just ran thru a bottle of the cheaper Castrol Syntrac Injector cleaner prior to changing plugs. Replaced fuel filter 6 months ago. Have AFE air filter.
Car idles smoothly, and above 3000rpm feels smooth, but that could be do to the engine spinning so fast and covering up the miss.
Do plugs ever foul that quickly? This happened within 20 minutes of changing. I had the battery unplugged the entire time I was changing them, and have reset the PCM after to see if that would cure it.
