Motor dies
Thread Starter
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Joined: Apr 2005
Posts: 94
Likes: 0
From: RedOak Texas
Motor dies
Hi Guys, My son has a 96 model. After running awhile the Motor dies and after setting and cooling down it will start. Sometimes in AM it wont start at all. 
Can anyone shed some light on this as where to start looking. Wish it were a C-3 lol
Thanks Guys
Can anyone shed some light on this as where to start looking. Wish it were a C-3 lol Thanks Guys
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Mileage? Does it run smooth when it starts? Mods?(including exhuast/headers) LT1/LT4 ? Very hard to say from all you have given us here, but early guess it may be fuel delivery issue causing vapour lock. (although thats ONLY a guess)
Team Owner
Joined: Aug 2000
Posts: 40,156
Likes: 45
From: San Pedro CA
I don't accept vapour lock as a problem with a modern injected engine. If nothing else, 45psi at the rail will stop vapour lock!
I am betting on the ignition module or the ECM. It's time to get ahold of a Helm Manual, www.helminc.com, and start debugging.
Helm publishes GM factory service manuals.
I am betting on the ignition module or the ECM. It's time to get ahold of a Helm Manual, www.helminc.com, and start debugging.
Helm publishes GM factory service manuals.
Melting Slicks
Joined: Oct 2004
Posts: 2,510
Likes: 4
From: Austin Texas
The first step would be to see if the ECM has any stored error codes. You can do this yourself with a short piece of wire, or a paper clip.
Procedure:
1) engine off, keys out of ignition
2) short pin4 and pin 12 on your ALDL connector located under steerring wheel to the right, kind of where your knee is located.
3) turn on ignition, but DO NOT start engine
4) Read error codes where your gas gauge normally displays
5) a C12 should be your first code, which is normal and indicates beginning of error code dumpage sequence.
6) Record any codes that pop up after the C12...
If you have any errors, you can cross referance the code(s) to your engine type here:
http://www.troublecodes.net/GM/
Yeah...I was a C3 guy for 15 or so years before I got my C4..quite a world of difference ehh!!!!
Procedure:
1) engine off, keys out of ignition
2) short pin4 and pin 12 on your ALDL connector located under steerring wheel to the right, kind of where your knee is located.
3) turn on ignition, but DO NOT start engine
4) Read error codes where your gas gauge normally displays
5) a C12 should be your first code, which is normal and indicates beginning of error code dumpage sequence.
6) Record any codes that pop up after the C12...
If you have any errors, you can cross referance the code(s) to your engine type here:
http://www.troublecodes.net/GM/
Yeah...I was a C3 guy for 15 or so years before I got my C4..quite a world of difference ehh!!!!
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
Originally Posted by bogus
I don't accept vapour lock as a problem with a modern injected engine. If nothing else, 45psi at the rail will stop vapour lock!
I am betting on the ignition module or the ECM. It's time to get ahold of a Helm Manual, www.helminc.com, and start debugging.
Helm publishes GM factory service manuals.
I am betting on the ignition module or the ECM. It's time to get ahold of a Helm Manual, www.helminc.com, and start debugging.
Helm publishes GM factory service manuals.
Last edited by Casethecorvetteman; Dec 4, 2005 at 03:08 PM.
Burning Brakes
Joined: Nov 2005
Posts: 848
Likes: 1
From: 1992 LT1 6 speed Cayman Islands
Check for loose connections
I just fixed a exact same problem on my 92 today after buying new coil, ICM and ECM and 3 weeks of pulling my hair out.(see my thread 92 LT1 wont start - ECM?) and the problem ended up being the plug on connector for the ICM was shorted internally ( looke fine but lost contact intermittantly after warm up).
Stick with the simple things first like grounds and connections between ECM and ignition and try not to get frustrated like I did and start buying parts before isolating the problem.
Check the connection on top of the manifold, the one to the ICM (bolted to the coil bracket), the coil, and the opti one at a time by jiggleing each one around while someone tries to start the car to see if it will start> I was able to isolate the plug to the ICM this way.
Hope this helps.
Jerris
Stick with the simple things first like grounds and connections between ECM and ignition and try not to get frustrated like I did and start buying parts before isolating the problem.
Check the connection on top of the manifold, the one to the ICM (bolted to the coil bracket), the coil, and the opti one at a time by jiggleing each one around while someone tries to start the car to see if it will start> I was able to isolate the plug to the ICM this way.
Hope this helps.
Jerris
