Please help me with my 89?
Thread Starter
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Joined: Aug 2007
Posts: 54
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From: Calgary Alberta
Please help me with my 89?
Hi,
I have a 1989 corvette and a lot of problems that I feel are all conected to one. The car is in great shape with only 100,000km. It has been parked for a few years. My problems are as follows, it will run beautifuly and then with no worning the check engin light comes on and flashes and it can't hold its idle, the sterio speakers cut out the car surges realy bad stalls at every light the temp gage lies only one fan will turn on the modual for the fans starts clicking the climet control display starts flashing. I realy need help because I have no idea were to start please help me..
Thank you!
P.S
I have had the car checked for codes, when the loght is not on and running good it says no codes.
When the car is checked with the check engen light on the car wont talk to the computer.
I have a 1989 corvette and a lot of problems that I feel are all conected to one. The car is in great shape with only 100,000km. It has been parked for a few years. My problems are as follows, it will run beautifuly and then with no worning the check engin light comes on and flashes and it can't hold its idle, the sterio speakers cut out the car surges realy bad stalls at every light the temp gage lies only one fan will turn on the modual for the fans starts clicking the climet control display starts flashing. I realy need help because I have no idea were to start please help me..
Thank you!
P.S
I have had the car checked for codes, when the loght is not on and running good it says no codes.
When the car is checked with the check engen light on the car wont talk to the computer.
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Sounds like your ECM is bad or has a faulty electrical connection.
Le Mans Master
Joined: Aug 2003
Posts: 9,884
Likes: 3
From: Magnolia Mississippi
St. Jude '03-'04-'05-'06-'07
you can check for codes yourself, right after it happens, the codes stay until you disconnect the neg cable for 15-30 sec. If you search general or tech you can find the paperclip procedure on how to get the codes, and web site that lists what those codes rep... also FSM is the best investment
Pro
Joined: Oct 2004
Posts: 644
Likes: 15
From: Clarksville Tennessee
If your computer isn't showing any codes and you've checked the wiring under the hood and vacum lines for leaks.. then maybe you could have a problem with the computer. It's strange that it's running like that and throws no codes. Someone will chime in with a possible solution. 
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Check ECM power and grounds first. ECM will erase memory if one or the other is intermittent. Assuming they're good, and if you've removed the ECM at any time, make sure the PROM is fully seated. Failing that and if your MPG and RANGE function are on the fritz too (when the problem occurs), pretty good odds that you need a new ECM.
Last edited by SunCr; Aug 6, 2007 at 01:36 PM.
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
ECM Tap Test
Remove the ECM from under the dash - leave it hooked up & start the car. Firmly but lightly tap the ECM's outer housing with the handle end of a screw driver to see if the car's problems re-occur. If car stumbles during the test replace the ECM.
Thread Starter
Advanced
Joined: Aug 2007
Posts: 54
Likes: 0
From: Calgary Alberta
thank you all!!
I went out and bought a new computer and chip..All my probs are gone..Thank you all so much!!
Now all I have to do is replace the heater core. Is this an easy job or should I take it to a shop?
Thanks again
Zig's
Now all I have to do is replace the heater core. Is this an easy job or should I take it to a shop?
Thanks again
Zig's
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Burning Brakes
Joined: Dec 2000
Posts: 1,161
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From: Orangeburg, NY
The heater core is a fairly tough job, but not difficult, and can be time consuming. There are several posts on the Forum that can assist you. The best method is the one where you remove the front seat. There are two particular screws that are hard to get to, but I used a flex extention with a screwdriver kit.
Considering it is basically "one time" job, go for a good quality heater core.
Good Luck.
Considering it is basically "one time" job, go for a good quality heater core.
Good Luck.
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
But get the Service Bulletins too as it corrects all the mistakes (or you can download them at www.alldata.com for a subscription fee). Core is a matter of taking off parts until it's accessible. The Breadbox - at least for me - is always the biggest obstacle; otherwise, I just keep taking stuff off until it's easy.