T&c wont stay running
 

in the past this thing will cut out over a large bump like someone turned off the key for about 1/2 second not major but irritating all the same. today i was charging the a/c. suddenly it begins to die and will restart when i start it run for a minute or less then die again. i grab my fuel pressure guage and a timing light as ive been wanting to check this out and it has finally reared it's ugly head... fuel is around 55 psi and steady, but when it dies the timing light goes out before the motor stops turning so we got a electrical issue. im guessing possible grounding issue so heres my questions and some history.
trans has been rebuilt about 2 years ago so it was out.
i tapped lightly on the ECM with a rubber mallet nothin happened.
1. where are the grounds located?
2. are there any other wires that like to rub through and ground out?
3. Anything else that likes to do this?
thanks, Ted