Floating Gas Gauge

My girlfriend has a 1997 Lumina. The gas gauge seems to be pretty messed up. When the car is almost low on fuel the gauge will show half a tank left, or will show that the car is full. Could this just be the gauge or could it be a problem with a sensor? Thanks for any help!

I too have a 97 Lumina with the same problem... if you get any ideas, let me know.

Could be one of two things. Either the sensor in the tank...or the gauge cluster. GM's electronics aren't known for their reliability. :eek7:

Do you refer to full, or past full? Past full indicates that the sender is not connected to the indicator. This sounds to me like a sender issue. Try locating the sender wire, and do a resistance reading. Disconnecting the connector should send the indicator past full, shorting the wire to ground should indicate empty. If necessary, you may need to do a resistance reading on the sender, but this will require removal of the sender to check for a smooth resistance change as the sender moves. Ray

Have just atarted having this problem and joined forum looking for answer if I find solution will get back to you