I over tightened the bolt that attaches the wiring harness to the ECU and I think I broke something. Now I the bolt is loose, but I can't seem to take the ECU harness off. Any suggestions on how to fix this?

My guess is that there is a nut built inside the ECU that broke loose. Maybe if you clamp a pair of small vice grips on the head of the bolt and pull on it as you turn it, maybe you can get the bolt out. You may want to do this with the battery disconnected because if I am right, you will have a loose bolt rolling around on the printed circuit board.

Thanks, I'll take a closer look at this. Sounds like I might have to take that ECU out and open it up.

Gorilla tight on plastic? I'm trying to understand why some people have no clue when something is tight enough? We had a new tech ex-parts guy come to our dept. (I like Him) and he overtightens a -4 JIC fitting so damn tight he cracks the b-nut and it's steel!!!! I think most of you wanna be techs need to seat down and at least read that Standard torque for SAE and Metric fasteners (In the front of Most Haynes and Chilton Manuals) so you have an idea and feel for what's tight enough!!!!