Gas gauge stuck on F

Usually its the float on the fuel pump, in the gas tank being stuck or not working. Maybe a frayed or bad elec connection from pump to gauge. Or even gauge itself. You could jus keeingp track by getting gas at a preset mileage like ur probably doing now.

it could be the wire to float sensor is hitting ground, you would have to check wiring to sensor, i would check that before replacing float sensor, i believe you would have to get the whole fuel module to replace sensor,

Before you tear into the tank sensor, try replacing the fuel data center in the dash. My 93 DeVille had similar problems and a little internet research lead me to the data center or BCM. A functional data center on Ebay set me back $150 but it was plug and play to install it. About a 1/2 hour job (25 mins disassembling and reassembling the dash pieces and 5 mins to remove and replace the data center).

float stick keeps going back and fotrh