Fuel pump does not work

OZZIESSTANG

MEMBER
1987 FORD BRONCO
V8
4WD
AUTOMATIC
76,000 MILES

The vehicle turns over well, and I am getting spark but the fuel pump (new) does not run unless it is grounded out at the self test plug. I tried pulling codes to see if I could get any answers from the computer, however I cannot get any which leads me to believe the previous owner simply had the fuel pump grounded due to a wiring problem. Hmm. The engine runs fine when pump is grounded, but I assume it should not be grounded for the long run. Please lend some advice. thanks

1 Reply

DAVE H

MECHANIC
13,383 POSTS

Check all wiring from pump. Also, have you checked Inertia Switch under dashboard at right of transmission hump?

Some fuel injected models use an electrical interrupt switch in the fuel system. On Ford Motor Co. Vehicles an inertia switch is used. The inertia switch disables the fuel delivery system when the vehicle is struck violently or when vehicle rollover takes place. It is mounted in various locations, depending on the vehicle model.
Operation:
In the event of a collision or vehicle roll-over, electrical contacts within the inertia switch shut off fuel supply to the electric fuel pump. Fuel supply will be interrupted even if the engine is still running. Switch contacts are normally closed, but open upon impact or roll-over. A reset button is located on the switch assembly. If the electrical circuit trips, it is not possible to re-start the vehicle unless the switch is reset by depressing the re-set button. Anytime the switch opens, the fuel system should be inspected for damage prior to resetting.