1999 GP GTP rough idle and acceleration
I have an '99 GTP that has about 209,000 miles on it.
Lately, as far as about late June to early July, it had a rough idle when I started it one day. Under acceleration, the "roughness" would get worse at about 2500 rpms. So far, it'* just getting slowly worse and I can feel vibrations in the gas pedal and steering wheel when accelerating, and the car vibrates when stopped and in gear.
I replaced all of the plugs and wires and that seemed to work for a bit, but then the vibrations come back.
I've read that the metal heat shields that go over the rubber on the plug end of the wire can cause a short and the plug won't spark properly sometimes. I haven't tried that, yet and won't unless some say it'* a good idea.