Electrical Problem
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Joined: Nov 2005
Posts: 66
Likes: 0
From: Cherry Valley il
Electrical Problem
My brothers 1990 Coupe hasan electrical problem we are trying to figure out, wondering if anyone can help out.
The car will start and run fine for awhile, then just die and won't restart. Inectors ohm'd good.
Strange thing is, all the relays under the hood and dash will cycle, the fans turn on and off, a/c clutch engages and turns off, no injector pulse, no spark, but the car will crank.
I have no idea what would cause all these electronic components to turn on and off rapidly. If the car sits for 30 mins it will start right up again. While we were checking things today, just having the key in the on position for a few minutes will cause this to happen and the car won't start......
any ideas??
Thanks
The car will start and run fine for awhile, then just die and won't restart. Inectors ohm'd good.
Strange thing is, all the relays under the hood and dash will cycle, the fans turn on and off, a/c clutch engages and turns off, no injector pulse, no spark, but the car will crank.
I have no idea what would cause all these electronic components to turn on and off rapidly. If the car sits for 30 mins it will start right up again. While we were checking things today, just having the key in the on position for a few minutes will cause this to happen and the car won't start......
any ideas??
Thanks
Safety Car
Joined: Jan 2006
Posts: 3,566
Likes: 4
From: Mt Laurel NJ
St. Jude Donor '06-'07
When it's running, check the alternator output. Also check the wires from it, to make sure it is charging the battery. I sounds like the alt is not working, and the car is running off of the battery. With the engine running, you should see 14.4 volts at the battery. You could also have a bad cable.
Let us know what you find.
Randy
Let us know what you find.
Randy
Le Mans Master
Joined: Jan 2006
Posts: 5,621
Likes: 206
From: Orlando FL
All those things you talk about are ECM related. There is a good chance the ECM is bad but I would first check grounds, connections, connectors and any voltage feed to the ECM. But if its really heat related could be the ECM.
You might try getting a big bag of ice an putting it on the ECM and see if you can effect it or get a warm feeling it its there. Its been done before but never have done it myself.
You might try getting a big bag of ice an putting it on the ECM and see if you can effect it or get a warm feeling it its there. Its been done before but never have done it myself.
Last edited by pcolt94; Jun 22, 2009 at 03:58 PM.
Melting Slicks
Joined: Dec 2008
Posts: 2,772
Likes: 64
From: Mystic CT
My brothers 1990 Coupe hasan electrical problem we are trying to figure out, wondering if anyone can help out.
The car will start and run fine for awhile, then just die and won't restart. Inectors ohm'd good.
Strange thing is, all the relays under the hood and dash will cycle, the fans turn on and off, a/c clutch engages and turns off, no injector pulse, no spark, but the car will crank.
I have no idea what would cause all these electronic components to turn on and off rapidly. If the car sits for 30 mins it will start right up again. While we were checking things today, just having the key in the on position for a few minutes will cause this to happen and the car won't start......
any ideas??
Thanks
The car will start and run fine for awhile, then just die and won't restart. Inectors ohm'd good.
Strange thing is, all the relays under the hood and dash will cycle, the fans turn on and off, a/c clutch engages and turns off, no injector pulse, no spark, but the car will crank.
I have no idea what would cause all these electronic components to turn on and off rapidly. If the car sits for 30 mins it will start right up again. While we were checking things today, just having the key in the on position for a few minutes will cause this to happen and the car won't start......
any ideas??
Thanks
Burning Brakes
Joined: Aug 2000
Posts: 1,146
Likes: 2
From: Albuquerque NM
My Orielly;s parts store has a neat module testor...that way you know for sure.
The fuel pump relay is another culprit...it is the third real from the drivers set. Mine has five relay underneath the passenger dash.
The oil pressure sender could also be the culprit has it keep the pump going as well as the fp relay.
The fuel pump relay is another culprit...it is the third real from the drivers set. Mine has five relay underneath the passenger dash.
The oil pressure sender could also be the culprit has it keep the pump going as well as the fp relay.
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
No spark and no injector pulses comes from no reference pulses from the distributor. The pickup coil supplies pulses to the spark module inside the distributor which in turn supplies reference pulses, spark timing pulses, and electronic spark timing bypass pulses to the ECM. See if you have code 42 (electronic spark timing) and/or code 43 (electronic spark control) stored. A common failure for spark modules in the distributor is to fail when hot. They don't cost much and this is one instance where replacing a part is a reasonable repair attempt. The problem with having a parts place test your module is that it is cool and works properly at the store. Take a hair blow drier with you and heat the module up during test!!! You might also check the pickup coil when you cannot start the car.
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