Notice

We are currently running a 1-2 day turnaround on repairs this week but we will be closed from July 14th - 18th but you can still send your unit in for repairs during this time period for when we resume normal business operations on Monday July 21st. Please retain a copy of your tracking number when shipping your unit in to us for repairs since we do not send out notifications of your packages arrival.     

Faulty sender units are common to some GM vehicles, but generally speaking will start malfunction at the same fuel level every time due to wear at the sender grid.
Also, you may get a fault trouble code which is usually an indication of a faulty sender or circuit.
A malfunctioning gauge esp. on some GM vehicles will be stuck and not move at all or be off the scale altogether.