[Anonymous]

My 1999 Old Aurora with 4.0L V8. A while ago my gas gauge would start fluctuating when the tank was below a 1/4 tank. Then eventually would only read empty. My fuel pump went bad and I replaced the whole module figuring it would solve my gas gauge problem also, but It did not and my gas gauge still reads empty all of the time. How do I go about finding the problem on my car.

Reply: As long as the new fuel pump has the level sensor on it, then sounds like you have a wiring problem. Reading empty is an indication of a short to ground in the level sensor wire- that is the purple wire. If it were an open circuit, then the gauge would be full. You are going to need to follow the purple wire from the sender into the harness and find a short to ground. Pulling at the harnesses as you follow it and watch the gauge for fluctuation will give an indication to where the problem is.

[Anonymous]

I replaced my fuel pump and wire harness yesterday,but now my fuel gauge in dash pegs above full and tank is around 1/2. I disconnected hot and ground on battery,pulled fuses and unplugged tank harness and gauge stays fully pegged past full ? Is the ip gauge bad ? The oil pressure on top reads correct just the fuel read on bottom ? Thanks in advance!

REPLY: Going full or past full with the harness at the tank disconnected is normal. This is an open circuit. When the tank is full, the level sensor reads high resistance- on a properly functioning car. Disconnecting the harness is the same as high resistance- millions of ohms, so of course the gauge reads full. You have a bad level sensor ! It is what you said- a JUNK yard part ! Test the harness from the tank and the gauge in the dash by grounding the level sensor wire on the car end- not the tank end. You will see the gauge go to empty.

REPLY: Could I take a good stout gauged wire and cut a U-like end connector and insert one end to black spade and insert other blade end to purple spade and see if what reads is opposite which of course is at the top frame channel end or car end of wire harness ???

REPLY: Yes. Assuming the black wire is a good ground, then you are completing the gauge circuit with 0 or low resistance- so the gauge will go the opposite way from having an open circuit.

REPLY: THANK YOU ALL!! Now will the gauge peg emptiest or if ground works show with in reason like between 1/4-1/2 like it looks pulled out inside tank ?? In other words will this show a reasonable reading or does tank have 2 b pulled again and something else done ???? THANKS IN ADVANCE 2 U ALL !!!!!

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