In my 98 GT. I was driving to school last night after doing about 1 and half hours of highway driving. I come to the first stop light and the engine started to vibrate extremely rough, although the rpms were still around 700 at idle. Also, the car seems to really hesitate when cruising between 1500 and 2200 rpms. This happens in both 3rd and 4th gear. Any ideas?

 

Fuel filter? Plugs? Wires? When was the last time you changed all that?

 

Havent changed the fuel filter. The plugs i changed. The wires seemed to be okay. Im thinking about changing the coil packs and maybe try some of the Seafoam stuff to clear out the carbon build up in the intake.

 

+1 on the coilpacks... sounds like detonation or misfire.