Does anyone know the cause and repair of gas guage failure? Also, range on computer not working

 

The signal from the sending unit in the tank provides the signal for the gauge level and the computer. If the level is incorrect the computer will not calculate correctly. I am betting the fuel level control in the tank is defective or a wire to the connectors. I would clean and make sure the connectors are tight on the tank prior to pulling the control unit from the tank.

 

Check your sending units, or if there are more electrical failures it could be the rear sam control module. Take it your your local indie shop and have them check it out.