94 GMC Jimmy 4X4 ECM question, not starting

70SIXSPEED

MEMBER
1994 GMC JIMMY

Ok, my Jimmy started running rough last weekend. It recently got to the point where it barely ran and it had no brakes. The "Service Engine Soon" light was flashing (only sometimes though). So before I pulled the code I replaced the dist. Spark plugs, plug wires, vacuum lines, and intake hose. None of this actually seemed to make the truck run better. So I backed the truck into my driveway and pulled the codes. It came up with #32. I checked the book and this shows the EGR valve. The problem is that when I shorted the wires out to pull the code, I accidentally did it when the ignition was on, and I'm curious if I fried the ECM because right after I pulled the codes I tried to start it, and it fired a cylinder or two, but eventually stopped firing all together. I cleaned the EGR and that did not help, and then I noticed (after lots of trying to start it) that fuel was dripping from the exhaust. So currently I cant get it to fire, I checked the coil also and it is good. So Im starting to think I fried the ECM since it wont even try to fire now. Sorry so long, just wanted to include all the info I can. Thanks in advance!

1 Reply

KENVCR

MEMBER
105 POSTS

After all of these events have you ever disconnected the battery? If no unplug for at least a couple of hours. This will reset or zero out any stored info on the computor. Then when you hook it back up try starting it as normal. If it starts we can go from there. If no start or crank at all then you have caused total failure to the computor. Replace it with a used one from a wrecker if possible. Be sure to take yours out firts and get the exact match only.
If it starts and it still runs rough. Just cleaning the egr wont help. The internal parts are worn out it must be replaced. YOU NEED TO KEEP THE ORIGINAL TO GET THE PROPER REPLACEMENT. THE NUMBER STAMPED ON IT IS VERY IMPORTANT. Again after replacing any part undo the battery while you do this work. We you rehook up the comp. Will assume that the system part is normal and fire accordingly. Make damn sure that the electrical connections are tight. Code 32 will be displayed for at least 3 things.
Faulty Egr valve, temp switch or vacuum supply. Most likely of the 3 is the valve itself. Cost about $60 us or in Canada over a 100.
Good luck.
Let us know what happens.
Kenvcr