Intermittent high idle - an ECM problem
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Melting Slicks
Joined: Mar 2008
Posts: 2,351
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From: Delta B.C. Canada
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Intermittent high idle - an ECM problem
Been trying to resolve an intermittent high idle problem which only happens when re-starting after operating temp is reached. Revs eventually drop to normal. Cleaned TB, replaced IAC, no vac leak etc. My new vette mechanic diagnosed it as an ECM problem. In fact, if it's in high idle, and you tap the top of the ECM, the idle drops to normal right away. The bad news is that '92 ECM's are apparently impossible to find, so sending it off and re-building my old one is the only option, at a cost of $400-500. 
Has anyone here ever had this done, and where? Or, does anyone have a secret line on a gauranteed good one?
Has anyone here ever had this done, and where? Or, does anyone have a secret line on a gauranteed good one?
Safety Car
Joined: Jun 2006
Posts: 3,629
Likes: 28
From: FL
Been trying to resolve an intermittent high idle problem which only happens when re-starting after operating temp is reached. Revs eventually drop to normal. Cleaned TB, replaced IAC, no vac leak etc. My new vette mechanic diagnosed it as an ECM problem. In fact, if it's in high idle, and you tap the top of the ECM, the idle drops to normal right away. The bad news is that '92 ECM's are apparently impossible to find, so sending it off and re-building my old one is the only option, at a cost of $400-500.
Has anyone here ever had this done, and where? Or, does anyone have a secret line on a gauranteed good one?
Has anyone here ever had this done, and where? Or, does anyone have a secret line on a gauranteed good one?
http://cgi.ebay.com/ebaymotors/ws/eB...K%3AMEWAX%3AIT
All of these companies claim to rebuild them, one is a forum vendor, I have no experience with any of them.
http://www.siaelec.com
http://gmautocomputers.com/
http://www.bsecorp.com/
http://www.autoecms.com/
I have used a local Florida company to rebuild the PCM in my Dodge truck with excellent results, I asked him at the time if he could repair the 92/93 Vette ECM's and he indicated that he could. The only contact information I have is an e-mail address,
acquaauto@aol.com his name is Louis. Good luck.
