no start 87 2.9

I have an 87 4x4 2.9. I know that the fuel system relay is not energizing. Both fuel pumps work, have changed the relay, even changed the cpu. The only way I can get it to energize the relay is to go to the test plug on the left fender well and run a ground from the far right terminal to the battery ground. The way I figure it is that there is a ground not making a connection. I can't remember if I ran a gnd from the battery to the gnd next to the computer or not. The other cpu i hav is used (and is the same numbers)- is ther a chance that it could have the same problem? Please help

I have an 87 4x4 2.9. I know that the fuel system relay is not energizing. Both fuel pumps work, have changed the relay, even changed the cpu. The only way I can get it to energize the relay is to go to the test plug on the left fender well and run a ground from the far right terminal to the battery ground. The way I figure it is that there is a ground not making a connection. I can't remember if I ran a gnd from the battery to the gnd next to the computer or not. The other cpu i hav is used (and is the same numbers)- is ther a chance that it could have the same problem? Please help

I believe the ECU needs two grounds. There's one in the cab and one directly from your battery. Are these both hooked up?

I believe the ECU needs two grounds. There's one in the cab and one directly from your battery. Are these both hooked up?
The one in the cab is grounded from the wiring harness next to the cpu to the cab. I will check the ground from the battery tomorrow. The gnd from the battery should go to the frame-should there be another gnd from the battery terminal going into the harness back toward the cpu? I came to the conclusion that the problem should be a gnd problem.

The gnd from the battery should go to the frame-should there be another gnd from the battery terminal going into the harness back toward the cpu? I came to the conclusion that the problem should be a gnd problem.

Yes that is correct, you should have a nicely sized ground going to the frame. You also have a smaller 14-12? gauge wire going from the battery into the main harness that goes to the ECU. Look for a black plug that's not hooked up kind of near the alternator/passenger side..

The one in the cab is grounded from the wiring harness next to the cpu to the cab. I will check the ground from the battery tomorrow. The gnd from the battery should go to the frame-should there be another gnd from the battery terminal going into the harness back toward the cpu? I came to the conclusion that the problem should be a gnd problem.
Pete, you are a genius. That was the exact problem. We were pulling stumps out and the battery had just enough movement to pull the plug apart.

Thanks again, Brian