djvski

I am looking at replacing the ECM on my 91 trofeo and wondering if anyone else has done this and what the steps are to taking it out. Has anyone out there done this before? I have the shop manual but can't find anything in it to help me. Your help would be greatly appreciated.

joe_padavano

Are you sure it needs to be replaced? ECM failure is rare (but not unheard of) and many, many times the problem is something else.

I don't know where you're located but I was at Crazy Ray's wrecking yard in Jessup, MD Sunday and there was a nearly complete Trofeo in the yard. I had not really paid much attention to that vintage Toro before, but it's really a cool little car. Up close it's much smaller than it appears on the road.

J-(Chicago)

I have heard of a few cases of the ecms going out on those cars. If you got another on the cheap, I suppose it's worth a shot replacing it. A friend of mine had a 91 cutlass, and I believe his car troubles were with the coil packs however.

Olds64

I had a 93 Buick LeSaber that I replaced the ECM in. Before you buy a new ECM and start taking your car apart you need to buy a service manual. For a 91 Trofeo I would suggest a Chilton's manual. You don't need to spend big bucks to get a factory service manual for a car that is your daily driver, but a Chilton's manual will have the ECM replacement procedures you are looking for.

When I did the ECM on my Buick it was due to a Quad Driver Module failure (part of the ECM that actually went bad). I asked around a dealerships and auto shops and found out it was much cheaper to do the repair myself than having someone else do it. I think I spent about $120 on a new ECM from the auto parts store and took about 2 hours to take out the old one and install the new one. It was behind the glove box in my Buick so I didn't have to take many parts out of the car.

Ultimately, if you decide to replace your ECM you need to use an anti ESD (electro static discharge) device when you handle the new one. This might be the hardest part of the job because they might be hard to come buy unless you have a friend that works in electronics. An anti ESD device is just a braclet that attaches to ground either through an anti static mat or straight to a ground point on your car. Whatever you do DON'T handle a new ECM without one of these. You will be throwing away your money!

djvski

Thanks for the help. The error codes I get indicate that it's a Quad Driver Module failure. I have the replacement ECM but thought I would ask around about how much trouble it is to remove the ECM from under the dash on this particular vehicle. The BCM is located right near and is easily removed. But I can't really tell what steps are necessary to get the ECM out. I have the Oldsmobile shop manaul but it doesn't tell me how to remove the ECM.