sackloltools
New member
- Nov 27, 2011
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when i release the brake pedal and roll at idle speed, the engine seems to make the car jump up and down as if i were rolling over a bunch of little speed bumps. but as soon as i press the accelerator it goes away. service engine light came on for a while and went away. went to autozone and the code reader came up with "misfire cylinder 1". i recently replaced the plugs and wires, could it be time for new coil packs? my car has 117,000 miles and its a 2003 pontiac grand prix se. (3.1L GM v6) automatic. could a dirty fuel filter do this? i just dont want to go spending money on parts i dont need just shooting in the dark. thanks!