patgizz Posted September 30, 2007 Report Share Posted September 30, 2007 at idle my tach is reading 2,000 rpm. hooking up to the #1 plug wire with the engine analyzer nets ~600 rpm, the true engine speed. it will then rev up to the reading of 5500 on the stock tach, which is only giving me about 3500 usable rpm and cutting out around 4100. i suppose i could start throwing known good parts at it, but where to start? start with an ICM? Quote Link to comment Share on other sites More sharing options...
GOT2B GM Posted September 30, 2007 Report Share Posted September 30, 2007 Are you revving it in park? There is a rev limiter in park and neutral at approx 3500 rpm. The gauge clusters in TGP's are known to go bad. That is most likely your only problem. Quote Link to comment Share on other sites More sharing options...
patgizz Posted September 30, 2007 Author Report Share Posted September 30, 2007 this is tried in gear, not park(trans is cooked so i can rev it as high as i need without moving) Quote Link to comment Share on other sites More sharing options...
90TGP Posted October 1, 2007 Report Share Posted October 1, 2007 You might want to check the Idle Air Control sensor. I know one day, the TGP was at idle, but I was going through a parking lot at 25mph. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.