have a 1994 grand am 4door se with quad4 4cyclinder its runnig rough I've replaced coil packs, spark plug boots, the howsing for coil packs still has a miss to it havent changed plugs yet.
Changing the plugs would have been one of the first things I would have done. Buy a premium plug with a single electrode and a platinum or iridium tip. The Grand Am coils spark two plugs at the same time and that wears out the cheaper plugs. Go to RockAuto.com for a good selection.
Had a friend with a 93 holds with the same engine doing the same thing. Pulled the vacuum line off the fuel pressure regulator because it was moist at the regulator and the diaphragm had ruptured spilling fuel into the intake. Worth a look.
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