fuel gauge inaccurate

what is wrong with your fuel gauge? not working?

when fuel is empty gauge still shows there is fuel in the tank.

the diagnostic start on this would be to check for DTCodes, there is a code for the sending unit, is the check engine light on? The gauge is controlled by the float in the gas tank. I would start at the tank with the float/sending unit. With a multi-meter check the resistance of the unit while moving the float up and down. Considering all the information for the dash gauges is send on a data wire from the ECM and its only the fuel gauge acting up. Start at the tank, make sure the ground wire has low resistance also. Here is a wiring diagram to help (wires are highlighted in yellow). I have seen many sending units in the tank go bad. Hope this helps.