Before starting the tests, find out how much fuel is in your 
Fuel Tank. Remove the fuel tank from the vehicle. Tear the 
Fuel Pump/fuel Level Sensor out of the fuel tank, keeping note that vehicles with T100 engines have a second fuel Level Sensor attached inside the tank. Connect ohmmeter probes to the wiring connector and read resistance on the 200-ohm setting. Compare sensor resistance with the float arm in two tank conditions: dropped down to empty, then lifted up to full. The resistance needs to vary smoothly between those two states. As the fuel tank empties, the sensor should show a reading around 110 ohms; when the tank is completely full, the value should be around 3 ohms. When the readings aren't right, get a new sensor. First take off the fuel pump/fuel Level Sensor assembly from the fuel tank, move the sensor carefully away from the opening without breaking the fuel level float on the bottom, disconnect the electrical connectors from the sensor, unscrew the tiny screw holding the bracket, and then take the sensor off the assembly. Installation is the reverse of removal.