Having problems with your Cars & Trucks ?
2004 grand am idles up and down
\015 From 600 to 900 rpms and when you put in drive or reverse the tranny knocks hard. Its not a mass air flow sensor. checked everything for a vacuum leak, not that either. unbolted catalytic converter, didnt change.\015
Have you checked for vac leaks, and is the transmission moving when you hear the knock ?
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