Q: Fuel gauge doesn't work correctly

It sounds like either the gauge itself may have failed or the sending unit for the fuel gauge that is connected to the fuel pump has failed. On most vehicles there is a floatation device that is connected to the fuel pump that will rise and fall as the fuel level does. This floatation device is connected to a sensor that produces a specific voltage based on the position of the floatation device. This voltage is then sent to a computer which then transmits that data to mean a specific value. This value is then turned into another voltage which is then sent to the fuel gauge causing the needle to move to a specific location.

If the floatation device is broken, this can cause your fuel issue. If the electronic portion of your fuel gauge still works (miles to empty), this would likely mean that the gauge is faulty due to the fact that the computer is still able to determine a value that is relative to the level of fuel in the vehicle.

If you’d like to get this repaired, contact a certified mechanic who can diagnose the problems with the gauge and replace the fuel gauge sender if necessary.