Need help now - removing 82 ecm
Thread Starter
Le Mans Master
Joined: May 1999
Posts: 6,692
Likes: 29
From: Texas
Need help now - removing 82 ecm
Have a replacement 82 ecm to install but cannot figure out how to remove the existing one. Somewhere I thought I read that it is an easy thing. Just 4 screws to remove. But I cannot determine where these 4 screws are. And, if I am guessing where they might be, they look far from easy to access. Anyone have a schematic or experience in doing this replacement. Stalled until answers. Thanks.
Instructor
Joined: Dec 2009
Posts: 199
Likes: 35
From: USA
I changed mine maybe 10-15 years ago, so I don't quite remember. But I think I removed the rear compartment frame and then battery. At this point you could get to the two top bolts and two bottom bolts.
Thread Starter
Le Mans Master
Joined: May 1999
Posts: 6,692
Likes: 29
From: Texas
1. Remove battery
2. Remove frame for compartment lids - gives just enough extra needed space to work
3. Two bolts on bottom, two bolts on top. 10mm, of course, metric. Fortunately for me, one of the bolts on the top was not there. Probably never there as this is the original ecm. Bottom ones are difficult to get to, but not impossible. One on top more difficult. Working by feel only. Mine existing one was on transmission tunnel side. I would hate to try to get to the one on the driver side.
4. Connectors held in place with built in clips. Use flat head screwdriver to press down on connector and wiggle connector loose and out. Probably tight since probably never taken off before.
5. Remove computer chip from old ecm and put in new ecm, matching up the notch if you don't still have the carrier.
6. Think I will apply some dielectric grease to connectors. They look clean, but want to make a good connection. Maybe spray with some connector cleaner first.
Thread Starter
Le Mans Master
Joined: May 1999
Posts: 6,692
Likes: 29
From: Texas
New ecm installed but won't start. Will crank, fuel to TBI's, but won't start. There was a momentary soft pfump sound when starting to crank. Did I blow something. Will the car crank if the ecm fuse is blown. Trying to get to fuses is even harder than the ecm. Any ideas?
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Thread Starter
Le Mans Master
Joined: May 1999
Posts: 6,692
Likes: 29
From: Texas
good. now check for +12v on one side of injector pigtail with key on. if that is there then check the other side for a ground pulse while cranking. also check for spark. if there is no spark and no injector pulse, and ecm is powering up, and there is +12v at injector and distributor power connections, then perhaps you have a failed ignition module under the distributor cap. this is a pretty common failure for gm hei ignition systems. and if the car is acting exactly like it did before you swapped the ecu, then perhaps you should see if you can get your money and old ecu back
Have a brand new module and wiring harnesses that were working fine before all this. Wiring harnesses from DUI, so they are quality.