The most likely reason is the sender wire (that runs from the sender unit in the fuel tank) is earthing some where along its route.
In most cases the fuel gauge sending unit in the fuel tank has failed.
sending unit in tank could be bad!!
fuel gauge on my 99 buick centry custom stays at full , then drops to empty. Is there a fuse or relay that i can have my neighbor look at it
check your answer
broken fuel gauage sensor or possibly a broken fuel pump indicator
probably the sending unit. unfourtunatly the sending unit and fuel pump are made in one peice, so expect it to be expensive
either the fuel gauge needs replacing or the fuel gauge sending unit in the fuel tank is stuck
The most common reason for the fuel gauge in an Impala to stop at half full is a bad fuel sensor. The sensor is mounted inside of the fuel tank.
A common problem with Honda cars is that the fuel gauge is stuck on full. This problem is solved by replacing the gauge cluster.
Your fuel sending unit is not giving the correct reading to your gauge
Check the fuel gauge sending unit, located in the fuel tank. The sending unit could be stuck in the full position.
There is no reset for the fuel gauge. The sending unit in the fuel tank has probably failed.