1999 Pontiac Grand Am Q&A

1999 Pontiac Grand Am Question: had replaced all coils,ignition mudule,and plugs and still have mutiple misfire.

replaced parts and still the same no power and rough idle -
Answer 1
Sounds fuel or compression related. Have you checked compression or performed an injector drop test? -
Answer 2
Any other codes besides misfires ? Any ability to read live data? Access to a vacuum guage--easy check for valve related problems often overlooked is with an old-fashioned mechanical vacuum gauge. -