82 corvette crossfire help
Safety Car
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From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
WOW! You have more than likely multiple issues. The number one suspect of a high idle is a vacuum leak, but before I say anything more...Do you have a GM Service Manual? If not, get one. It is an absolute MUST with these cars to maintain them.
OK, now for the rundown. Check ALL the top plate bolts for tightness, it's a weak point for CFI. Next check the TB bolts, same thing. Next is the IAC's, are they working (cycling)? The IAC controls the idle and is a controlled vacuum leak.
You said you moved the dizzy, did you disconnect the EST wire before doing that? If not, the ECM was controlling the timing and not you moving the dizzy. You may want to recheck your timing now.
Do you or did you have a CEL? If so, what were the codes? Why did you replace the MAP sensor, just wondering? Hope some of this helps, so take one system at a time and not shotgun parts into it.
OK, now for the rundown. Check ALL the top plate bolts for tightness, it's a weak point for CFI. Next check the TB bolts, same thing. Next is the IAC's, are they working (cycling)? The IAC controls the idle and is a controlled vacuum leak.
You said you moved the dizzy, did you disconnect the EST wire before doing that? If not, the ECM was controlling the timing and not you moving the dizzy. You may want to recheck your timing now.
Do you or did you have a CEL? If so, what were the codes? Why did you replace the MAP sensor, just wondering? Hope some of this helps, so take one system at a time and not shotgun parts into it.
Zen Vet Master Level VII
Joined: Mar 2016
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From: Southlake, TX
This is really the best way to identify your issues. Please check your codes and report back!
Le Mans Master
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From: columbia city in
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Safety Car
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From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
The MAP sensor probably isn't bad, but you may have either a Ground, Short or Open in CKT 432 OR Ground, Short or Open in CKT 416 and then the ECM is probably bad if the above CKTs are good.
All you need is a manual and a meter to figure out what is bad.
Last edited by Buccaneer; Jul 13, 2016 at 08:16 PM.
Zen Vet Master Level VII
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From: Southlake, TX
Le Mans Master
Joined: Jul 2000
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From: columbia city in
if the map sensor has been changed and you are still getting a bad reading then you have to look at what is causing the bad sensor reading.I would check first were is your map sensor connected and do you have a vac leak.