my 87 ford f150. gas gauge stays past full even when empty whats wrong..?
when the switch is off the gas gauge from past full down to full
- NomaddLv 78 years agoFavourite answer
The pickup in the tank is bad or the wire to the pickup is shorted to ground. Assuming the needle goes down when you turn the key off.
From the additional details, it sounds like the gauge itself is bad. There is no ground wire to the sender. You have a steel tank, which itself is the ground. Even if it was plastic, the pump wouldn't be running if the ground came off.
- superb9006Lv 78 years ago
The ground wire for the sending unit has come off. Probably corroded. Check it on the sending unit and repair it.