1982 ECU Bad?
Thread Starter
Intermediate
Joined: Jun 2010
Posts: 39
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From: Whitehouse TX
1982 ECU Bad?
Hello,
I have a "new to me" 1982 Corvette that is an unmolested 68k mile vehicle. I drove this car back from Florida to Texas when I bought it a few weeks ago and it runs very well. I am trying to take care of all the hopefully "minor" issues. One issue is that the CEL light comes on and stays on. I ordered a OBDI USB cable but could not get any data to display. I then tried the "paperclip" method and could not get the CEL light to flash at all! So that leaves me pondering... I did try the simple plug and unplug the ECU to no avail... Any thoughts or suggestions? BAD ECU? Again the car seems to run fine but does have a issue of not taking fuel quickly if you "gas it" so to speak.
TIA
Dan
I have a "new to me" 1982 Corvette that is an unmolested 68k mile vehicle. I drove this car back from Florida to Texas when I bought it a few weeks ago and it runs very well. I am trying to take care of all the hopefully "minor" issues. One issue is that the CEL light comes on and stays on. I ordered a OBDI USB cable but could not get any data to display. I then tried the "paperclip" method and could not get the CEL light to flash at all! So that leaves me pondering... I did try the simple plug and unplug the ECU to no avail... Any thoughts or suggestions? BAD ECU? Again the car seems to run fine but does have a issue of not taking fuel quickly if you "gas it" so to speak.
TIA
Dan
Le Mans Master
Joined: Jan 2000
Posts: 8,918
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From: New Hill NC
Usually if the light is good, and the computer will not flash a code, either the computer or the chip is bad. But you should work through the trouble chart in the manual before passing judgement.
Le Mans Master
Joined: Jul 2000
Posts: 6,664
Likes: 162
From: columbia city in
http://www.crossfire.homeip.net/index.php?act=idxyou need this web site .can you tell us the two wires that you jumped with the paper clip?i am thinking that you did not jump the correct ones .http://crossfireinjection.net/both of these can help you.
Thread Starter
Intermediate
Joined: Jun 2010
Posts: 39
Likes: 0
From: Whitehouse TX
more info 82 ecu problem
Hello. I jumped the A and B pins which if you are looking down at the plug, bottom row, two pins next to each other, closest to steering wheel. Also, I have a new USB OBD1 Connector and could not get any data to flow, I even used hyperterminal to see if any data was present. CEL light comes on and stays solid, does not flash and does not go off.
Thanks so much
Dan
Thanks so much
Dan
http://www.crossfire.homeip.net/index.php?act=idxyou need this web site .can you tell us the two wires that you jumped with the paper clip?i am thinking that you did not jump the correct ones .http://crossfireinjection.net/both of these can help you.
Le Mans Master
Joined: Jul 2000
Posts: 6,664
Likes: 162
From: columbia city in
the part i dont understand is,you say the car runs okay but the light stays on.i think some one else has had this problem before .its on the cross-fire forum i will look to if i can find it .
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
The computer is not totally defunct or the car wouldn't run at all. At present, it may only allow the car to run in the 'default' mode, however, and never allow it to get to normal operation condition.
Does the transmission go into lockup mode? I believe that in 'default' mode, the lockup function does not work. If so, that might provide a clue as to what the ECU is doing.
You might want to disconnect the battery from the electrical system, and remove/clean/repair any direct ground connections to the ECU. Then try it again.
If that doesn't help any and the ECU doesn't get out of 'default' mode nor the OBDI system provide any fault codes, your ECU may have failed. As mentioned, you can plow through the diagnostic "tree" to see what you find. If you can't find any other problem(s), replacing the computer is the only thing left. They are now available from several of the Corvette aftermarket vendors...and they are affordable.
Does the transmission go into lockup mode? I believe that in 'default' mode, the lockup function does not work. If so, that might provide a clue as to what the ECU is doing.
You might want to disconnect the battery from the electrical system, and remove/clean/repair any direct ground connections to the ECU. Then try it again.
If that doesn't help any and the ECU doesn't get out of 'default' mode nor the OBDI system provide any fault codes, your ECU may have failed. As mentioned, you can plow through the diagnostic "tree" to see what you find. If you can't find any other problem(s), replacing the computer is the only thing left. They are now available from several of the Corvette aftermarket vendors...and they are affordable.
Thread Starter
Intermediate
Joined: Jun 2010
Posts: 39
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From: Whitehouse TX
Thanks so much for the great information, I was under the car yesterday adjusting the Ebrake and noticed that the main ground was covered in "gook". It look like it was solid and firmly connected but I will clean it and see whats up. I ordered a known working ECU w Prom from a member on this forum and hopefully will receive it maybe late this week. Thanks for all help!!
Dan
Dan
