My fuel gauge is driving me crazy. First it stayed stuck between 3/4 and Full. Figured it was a bad ground so I removed the ground wire from tank to frame and scuffed it and re-attached. While the wire was off gauge did nothing. Then I removed dash ground and gauge went to empty. Then I turned the key forward dash brake(idiot)light turned on and gauge went to 3/4 of a tank so I turn on the head lights gauge goes to E. Reconnected dash ground and key forward same damn thing brake light stays on and goes to 3/4 of a tank. I turned the key back needle goes back to E even with lights on. Confused Yea me too! And pretty ticked off! Now I know the damn thing doesn't have this much gas I've been driving it daily I know it is near E for sure. Thanks for the help in advance... Gabe
some gas tanks have a rubber seal ,between the sending unit and the tank, so the sending unit itself has to be grounded,also sending unit could be shot,float could be sinking(hole in it,filling with gas)or even you're gauge could be shot.also check that the body is grounded to the frame(ground strap).good luck! hope it works out!
Sounds to me like you have grounding issues. Power for the gas guage comes from an accesery power feed, then goes through the guage. After the guage the power goes to the sending unit where it grounds back to the battery through the chassis grounds. The sending unit in the tank is a reostat that veries the amount of resistance for the power wire to reach the ground. The guage measures the amount of resistance the sending unit is making before the ground to show how much fuel is in the tank. If you ground out the wire between the guage and the sending unit, the guage should read full. (someone will correct me if its the other way, every brand is set up differently) If you really get fed up with it, NAPA has a new gas guage and sending unit for around $40, I'm sure other parts houses have something similuar. The Napa guage/sending unit use the GM ohm base. Gene
I know this isn't what you're looking for. My Jeep's gas gauge has been off since I bought it new in 93. I learned how far I can go on a tank in the city, and keep track with the trip meter. I pulled the tank once to fix a leaking fuel line. It was such a pain in the ass. While I was in there I checked the sending unit, all the ground wires, and anything I could find that could possibly go wrong. Didn't work. If I ever find the guy who designed that set up...POW! right to the moon!
I had a lot of vehicles come in to work with same problems.On the chevy trucks there is a connection on top of frame rail in the drivers side rear wheelwell.Sometimes the connection gets corroded from water and such.Just my findings,hope it helps. Dan
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