Fuel guage works when it wants

The most likely problem is the fuel level sending unit in the fuel tank. It is a rheostat that is hooked up to a float in the tank. When the tank is kept at 1/2 tank or less than the rheostat stays at that spot and makes a open in the circut. When the circut is open or the resistance is low the guage goes towards full. When she fills it up the float rises to a spot on the rheostat that is not warn yet and works. The fix is to replace the fuel level sending unit in the tank or use the trip odometer to log how far she has gone on a full tank.

I would guess you will have to replace the sending unit in the tank. A mechanic can check the sending unit with a meter and find out if the sending unit is faulty or the gauge on the dash.

Yes, the sending unit is probably defective. Oil pressure varies at different engine RPM, oil viscosity and engine wear. Sounds OK to me. DT

u either have a bad level sensor in the tank or the guage is bad. u need to get wiring diagram and find connector for fuel sending unit and jump wires to trick guage into thinking it is full if it still say empty u need instrument cluster if it goes to full it level sensor in the tank

A loose connection on the sending unit could cause the problem but also moisture in the tank in cold weather could also be a factor in which i would add fuel line antifreeze to a full tank of fuel..........Hope this helps you out.

hi this sounds like it could be a couple of things, first the obvious have you checked the fuse? or it might be the relay in the fuse box might need replacing, and the fuel sender unit in the fuel tank, you also can check out the wires going to the sender unit, sometimes you can find these under the rear seat or in the boot/trunk area might be a simple case of one of the wires have come adrift there is a couple of things to check before having the sender unit replaced or the Gage..hope that helps

should be a grey wire going to the top of fuel tank connects to fuel guage / when the guage in the tank reads grounded it shows full , no ground it shows empty. if you ground that grey wire and the guage jumps to full then faulty guage if nothing maybe bad ground on the tank itself. the guages are a reostat like a tyco race car gun the more it moves the more it grounds .. good luck

your gauge is part of the integrated unit in the fuel pump module

Hi
We have the same truck that does the same thing.
The fuel sender in tank is faulty. It is in your gas tank. Common chevrolet problem.

The most likely culprit is the sending unit in the tank. They are relatively easy to change, as long as you don't have much fuel in the tank. It's a mechanical unit that has a float that raises and lowers with the fuel level, however with age, the floats can develop leaks and no longer float, of the electronic portion of the unit can go bad and not register the proper level. They are replaced and an entire unit, so it doesn't matter which happened, you will need to change the fuel tank sending unit.