Troubleshoot problem to fuel pump relay, no voltage to close the relay, Checked the ECC no volts at A1, Bad computer ???. Jumped pin A to E at the relay, Fuel pump runs. Replaced computer, still no volts at the computer A1 or pin c of the relay, Yes I checked the green/white wire, no opens /shorts. Bad computer ????. I need a specific wireing diagram if any one can send me one.It appears that the oil press switch is inthe fuel system some how .Need some help. Thanks

Oil pressure switch/sender will close a parallel circuit to supply power for the f/pump after oil pressure has risen enough to close the switch, usually after 12 seconds.

I believe the upon setting the ign key to "ON", the ECM powers the f/pump via the relay for 2 seconds. Then, the ECM will supply relay power to supply the f/pump power during cranking and engine ign on. If this event does not happen during cranking, oil pressure switch will close and supply power for f/pump.

Get a Haynes manual for a schematic, or better, visit a Mitchell CD Repair shop and ask for a schematic of the car and model. Offer to pay for it, even if they refuse payment. This will help troubleshoot and for other problems later with the car.

No FP relay volts at pin A1: TBI car with the '8746 ECM?

It may be the fuse. IIRC there is a fuse under the hood along the passenger side fender (US side of car). It is inline with a wire that runs from the front of the car to the firewall and into the passenger compartment. See if it is blown, if so, obviously replace it.

Check the fuses in the fuse block, drivers side under the dash.

It could also be 2 bad ECMs. It is common for the FP relay drive transistor to fail. At key-on, engine-off the voltage at pin A1 will go to 12 volts for 2 seconds. Then again for 2 seconds every time the ECM 'sees' a distributor pulse. So if the engine is running, always.

If you have a DVM check the FP relay coil resistance. Should be about 60 ohms. And no less then 40 ohms.

Bob.