Sender Unit Sticking

1. With the gauge in its stuck position, use a multi meter to monitor the resistance at the sender unit terminals.

2. Slowly pump out 0.8 gallons (3 liters) of fuel. Resistance should increase distinctly.

3. Slowly replace 0.8 gallons (3 liters) of fuel. The resistance should decrease to the original reading.

4. Slowly add an additional 0.8 gallons (3 liters). The resistance should decrease further to a reading lower than first measured.

5. If the resistance changes as described in steps 1-4, the sender unit is not defective. If no change in resistance was observed in steps 1-4 then either the sender unit is interfering with pipes or wires inside the fuel tank or the sender unit is defective. In either case, empty the fuel tank and remove the sender unit.

6. Look through the sender unit opening in the fuel tank and check for obstructions (pipe and wires) that may prevent free movement of the sender unit float and arm. Repair as necessary. Inspect the sender unit. The float should be free to rise and fall under its own weight. If not, replace the unit.