Computer Problems!!!!!
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Joined: Oct 2003
Posts: 64
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From: Norfolk VA
Computer Problems!!!!!
I own a 1990 Coupe. I love this car but if it's not one thing it's another. My present problem is that I'm not getting any spark. My buddy is convinced that my ecm has given up on me. Is there any way that I can check the computer to make sure that it needs to be replaced before I fork out the money. I am not very mechanicaly inclined to say the least, but with good instructions and the help of my backwoods neighbor I can fumble my way through many a project. Thanks in advance for any information you may have for me.
Team Owner
Joined: Dec 2000
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From: SE NY
Cruise-In II Veteran
Re: Computer Problems!!!!! (wildman23505)
The first thing is to pull any stored trouble codes, like this:
-locate the ALDL under the left hush panel, just right of the steering wheel
-insert the ends of a paper clip into pins A & B, upper right
-turn on the ignition key and count the SES flashes; there will be three "12s" followed by each trouble code three times and terminated with three "12s".
-turn off the ignition, remove the paper clip and post any codes here
-locate the ALDL under the left hush panel, just right of the steering wheel
-insert the ends of a paper clip into pins A & B, upper right
-turn on the ignition key and count the SES flashes; there will be three "12s" followed by each trouble code three times and terminated with three "12s".
-turn off the ignition, remove the paper clip and post any codes here
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Computer Problems!!!!! (wildman23505)
If you can pull stored codes at the ECM is still alive. I think the EST module gens the spark signal and the ECM simply provides a signal to control dynamic timing.
Have you checked the dist cap & rotor for any problems?
Did you check for spark by clipping a timing light onto a wire and watching for flashes as you crank the engine.
If all is well with the cap & rotor and you get no flashes, check the coil (resistance between the output & ground and resistance across the prongs for the Gry connector); if it's ok check for a voltage pulse across the leads of the Blk connector to the dist.
Have you checked the dist cap & rotor for any problems?
Did you check for spark by clipping a timing light onto a wire and watching for flashes as you crank the engine.
If all is well with the cap & rotor and you get no flashes, check the coil (resistance between the output & ground and resistance across the prongs for the Gry connector); if it's ok check for a voltage pulse across the leads of the Blk connector to the dist.
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Joined: Oct 2003
Posts: 64
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From: Norfolk VA
Re: Computer Problems!!!!! (wildman23505)
I checked for a spark and got nothing. I replaced the cap and coil. I was told that the rotor looked ok and because auto zone didn't have one in stock I didn't replace it. That's all I have done so far.
Racer
Joined: Apr 2001
Posts: 452
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From: Tulsa Ok, Racing the wind
Re: Computer Problems!!!!! (wildman23505)
The ECM's are running about $80. I just put one in my 88 and it fixed several problems I have had for 2 years. Hesitation and wrong temp readings. I was suprised the see them for that price, but it did fix up the old C4.
Got mine at Autozone, Pep boys and ORielly's have them too for a little more. Watch out the core charge is about $140, but you will get that back once you return the core. Good luck :yesnod:
Got mine at Autozone, Pep boys and ORielly's have them too for a little more. Watch out the core charge is about $140, but you will get that back once you return the core. Good luck :yesnod:
