BMW Repair: Fuel System trouble-shooting, 1986BMW325ES, fuel system trouble, fuel pump relay


Question

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Followup To

Question -
Don,
My car started and then died suddenly. I have spark, but no fuel. I've checked relays, fuses,and connections. I have power to the relays and fuse 11, but no voltage at either the transfer or fuel pump. Could the ECU be the problem? Any advise or suggestions would be greatly appreciated. Thank You, Robert Carreira

Answer -
Check the body ground as this is where the pump gets its ground.The ECU probably is not the problem.It is more than likely the ground.Check the ground under the rear seat.
Don, Thank you for getting back to me so quick!
I will try the ground you are talking about. I also found I have no voltage at fuse #11, or at terminal 87 on the relay. Would the ground you are talking about also affect this? Thank You for your help. Sincerely Robert

Answer
Term 87 will not have power until the relay is energized.Check the pump by taking a jumper wire from term 30 to term 87.The pump should run if not the wiring to the pump needs to be looked at.The car is old and the wiring has a tendency to corrode internally, the wires will be bumpy looking, a sure sign of corrosion.They would need to be cut and replaced with a soldered connection.
Having lack of power at #30 maybe due to the red wire from the battery to the junction block and relay socket.Check to make sure that the main relay is getting power as it powers the fuel pump relay.