Ford Crown Victoria/Grand Marquis 1989-1998

Fuel Level Sending Unit


The fuel level sending unit is located on the fuel pump inside the fuel tank.


Observe all applicable safety precautions when working around fuel. Whenever servicing the fuel system, always work in a well ventilated area. Do not allow fuel spray or vapors to come in contact with a spark or open flame. Keep a dry chemical fire extinguisher near the work area. Always keep fuel in a container specifically designed for fuel storage; also, always properly seal fuel containers to avoid the possibility of fire or explosion.

An assistant is recommended and extremely helpful for this testing procedure.

  1. Check the appropriate fuse before attempting any other diagnostics.
  3. Raise and support the vehicle.
  5. Unplug the fuel level sending unit connector from the top of the fuel tank.
  7. Insert the leads of the Rotunda gauge tester number 021-00055 or equivalent into the fuel level sender connector and set the scale to 145 ohms.

Although a gauge tester is recommended for the testing of the fuel level sending unit, you can purchase resistors of the equivalent value at any electrical store and form your own tool.

  1. Turn the ignition to the ON position and verify that the fuel gauge reads EMPTY . If the gauge reads EMPTY , proceed to the next step, if it does not, repair gauge and/or wiring as necessary.

It may take as long as 60 seconds for the gauge to move.

  1. Slowly turn the resistance level on the gauge tester to 22 ohms and verify that the gauge reading moves to FULL . If the gauges moves to FULL , the gauge and wiring are operating as designed, most likely the sending unit is faulty, repair as necessary. If the gauge does not read FULL , repair gauge and/or wiring as necessary.

An alternative method requiring no special testers is to remove the fuel pump from the tank. Connect the wiring to the pump and sending unit and manually operate the sending unit arm while an assistant observes the gauge.


The fuel level sending unit is attached to the fuel pump. Refer to Fuel System and the fuel pump removal and installation procedure.