The gauge, wiring or sending unit is bad.
You need to check the power and ground at the fuel tank. If that is okay the float is most likely bad.
Could be a blown fuse.
The fuel sensor is in the gas tank and probably needs replaced, the tank will have to come out to fix it.
You fill the car with gas, you use up all the gas, then you fill it up again!
the sending unit may be stuck
A Full tankful.
the fuse my be blown or ,it needs anew gauge
Because the car has a full tank of gas.
Bad fuel pump in rear tank?
for your gas gauge to tell you when your ride is out or full of gas
If it takes 30.00 to top off the gas tank, but the gas gauge shows full on an 85 F150 4.9 Straight 6, it is likely that the gauge is not reading correctly. Replacing the gauge cable can remedy this.
why won't my gas gauge work all the time.it will read full when i fill it but after that as i drive i am not sure how much gas is in the tank