'91 PCM - Can't get it out

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Black91SHO

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I'm trying to replace the PCM in my '91, but I can't seem to get it out. I removed the 7mm screw and bracket behind the glove box, then I started unbolting the 10mm bolt in the middle of the large connector under the hood at the passengerside of the firewall. That's where the problem comes in. No matter how many times I crank away at that bolt, the computer doesn't separate and come out. I've turned the socket wrench probably 300+ turns. No matter what I do, the plug doesn't separate.

What am I doing wrong?
 

AREA 91

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The bolt threads into a collar inside.
I have had that collar spin inside.
You can try pulling on the plug while you unscrew the bolt.
If that doesn't work, you will have to cut the head off the bolt, remove the computer, and find a replacement bolt.
BTDT! :(
 

Off Road SHO

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That 10 mm bolt just holds the wiring plug onto the PCM. The PCM is held into the firewall by a squish plate that squeezes a foam gasket and seals the PCM to the firewall.

Slowly pull the 60 pin plug off of the PCM.

Remove the two bolts, one on either side of the PCM under the hood. Pull the PCM to inside of car. I don't think you have enough clearance on the engine side.

Tom
 

rubydist

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but the connector is held onto the pcm by that 10mm bolt, and if it is just spinning then to get the connector off you will have to cut the head off the bolt.

the pcm needs to go into the passenger compartment. it is a tight fit on the gasket, so it hard to get wiggled loose.

I had one with the bad collar inside the pcm - after I got the pcm out, I took the cover off the pcm, put the collar back in place and epoxy glued it in place. Then I was able to attach the connector correctly with a new bolt.
 

Black91SHO

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Glad to hear I'm not the only one that has trouble with this.

I'll keep working on it. Maybe some pressure will help. Hope I don't have to cut the bolt...

Thanks.
 

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