I have a 1990 Bronco with 351W. Just this past weekend it snowed pretty hard here and my wife (of course) took the truck to work. When she came out at Midnight, nothing.
The next day I went out with my Haynes manual and eventually figured out the fuel pump wasn't operating. By using the diagnostic jumper (forces fuel pump to operate continuously while key is in run position), I was able to get the fuel pump running.

I removed the jumper and everything worked fine, for about 100 yards, then it cut out just like I had turned off the key. It's permanently jumpered right now and runs fine. Being and electronics technician, I figure the problem is somewhere in the control side of the fuel pump (when jumpered, the pump works fine and I know electronics are involved in the control of the pump because the EEC runs a 1 second engine off test on the pump prior to engine start, then shuts off at start up, this does not happen regularly anymore).
I figure I need to trace through the control side of the pump circuit to locate the fault.
I do not have any good wiring schematics of the fuel pump control circuit. Does anyone know where I could locate detailed wiring schematics for a 1990 Ford Bronco XLT with 351W and E4OD?

Thanks in advance.

 

Ford offers a service manual on cd, I have read form posts on here that you can sometimes find them on E-bay. Also did you check the relay and the inertia switch? The relay should be on the firewall, the inertia switch is either behind passenger kick panel or parking brake, I am not 100% sure. Check your owners manual if you still have it.
Good luck

 

I'll have to look into the service manual. I do know about the inertia switch, and I've checked it. Of course there could be an intermittant issue with it, but I'll have to rule that out. As far as the relay goes, it wouldn't hurt to replace it. Thanks for the reply will let you know what happens...