Gas Gauge 1999 Ford Expedition

1999 Ford ExpeditionFirst of all about a week ago my truck was hit from the rear while parked. Consequently It was hit hard enough to push the hitch to one side a bit. Since then, the gas gauge is not registering right and the car cuts out a lot. Hence, Could this be related?


Absolutely. A hit hard enough to tweak a trailer hitch can cause quite a bit of damage to anything attached. The gas tank is secured tot he frame of the vehicle. So it absolutely has been shaken hard enough to cause the gas gauge sending unit to move. Also, this could have caused damage to the sending unit arm and the fuel pump module that it is connected to. However a more likely reason would be that the impact jarred some internal rust loose. The rust would not have come loose otherwise. Furthermore rust would clog the fuel filter at times and interfere with the fuel sending unit readings. In Conclusion the fuel gauge worked and truck ran fine before it was hit and now it doesn’t. Pretty safe to say it was related since the impact was hard enough to tweak the trailer hitch. .

Fuel Tank and Lines

Component Location

gas gauge location

ItemPart NumberDescription
19030Fuel tank filler cap
29034Fuel tank filler pipe
39350Fuel pump
49002Fuel tank
59S278Rear fuel supply return and vapor tube
69155Fuel filter
79341Inertia fuel shutoff switch

The fuel system consists of:

  • a fuel tank.
  • the fuel tank filler pipe which contains a restrictor plate to permit only unleaded fuel to be pumped into the fuel tank.
  • a 1/8 turn type fuel tank filler cap.
  • a fuel filter providing filtration to protect the fuel injectors.
  • fuel lines.
  • fuel pressure regulator.
  • a fuel pump containing:
    • the electric fuel pump which provides pressurized fuel to the engine.
    • the fuel level sensor (9275).
    • an inlet filter.
    • a check valve which maintains system pressure after the pump is shut off.
    • a pressure relief valve for overpressure protection in the event of restricted flow.

The fuel pump is controlled by the powertrain control module (PCM) (12A650) which energizes the fuel pump relay. Electrical power to the pump is provided through the inertia fuel shutoff switch