idle problems again 85 corvette
Thread Starter
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Joined: Jan 2011
Posts: 57
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idle problems again 85 corvette
I replaced tps and iac checked everything by the book car run pretty good for about a week this weekend I drove to town about 15 min car sat for an hr would not idle had to keep foot on the gas to get her home I tried to crank without putting foot on gas nothing then a n hour later it cranked without giving gas but idled high about 12 to 13
thanks need help
thanks need help
Safety Car
Joined: Aug 2009
Posts: 3,745
Likes: 275
From: Melbourne, Victoria, Australia
Did you disconnect the battery ? after that the ecm will need to re learn to get your engine running smooth.
The manual shows the correct iac measurement before installing it.
The tps .54vdc should start and rev to 1,200 rpm and slowly drop to
600rpm
Thread Starter
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Joined: Jan 2011
Posts: 57
Likes: 0
What ... a 4bl carb= bucket with a hole ...er 4 holes
Did you disconnect the battery ? after that the ecm will need to re learn to get your engine running smooth.
The manual shows the correct iac measurement before installing it.
The tps .54vdc should start and rev to 1,200 rpm and slowly drop to
600rpm
Did you disconnect the battery ? after that the ecm will need to re learn to get your engine running smooth.
The manual shows the correct iac measurement before installing it.
The tps .54vdc should start and rev to 1,200 rpm and slowly drop to
600rpm
Thread Starter
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Joined: Jan 2011
Posts: 57
Likes: 0
rechecked iac and set at 450 in drive checked tps also checked for codes to start with nothing coming up pulled neg cable will run for a few days and see how it works out I also need to check vacum not sure the best place to pull from
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
There was a Bulletin on the '85 with a redesigned PROM as the IAC was relearning itself to 0 counts which makes it stall; difficult start etc. Dealer's were instructed to raise Min Idle to 500 rpms (or something like that). I'd get a copy of the Bulletin, check your PROM #.
Thread Starter
Advanced
Joined: Jan 2011
Posts: 57
Likes: 0
There was a Bulletin on the '85 with a redesigned PROM as the IAC was relearning itself to 0 counts which makes it stall; difficult start etc. Dealer's were instructed to raise Min Idle to 500 rpms (or something like that). I'd get a copy of the Bulletin, check your PROM #.
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