Help! Fuel Gauge is pegged past full

[Campbelmg]

My fuel gauge is pegged past the full line, I'm assuming that this has something to do with a bad ground ...if so would it be in the gauge cluster or the sending unit......or possibly something else?

 

[Vettehead Mikey]

It's not a bad ground, it's a full short.

 

[frank_nesta]

The gauge works in the following manner.. If you have power and ground.. and no input signal.. (Resistance from the senders get unit) the gauge will peg.. If you have a grounded out wire on the input (ohms wire) then the gauge will peg to zero...


You either have a break in the sender wire (or a bad connection at the sender) or the sending unit is bad.

 

[AlanEla]

How about if it pegs past full when it's not working properly, but decides to function sometimes? Loose wire that sometimes connects, perhaps? Mine is a '79

 

[frank_nesta]

How about if it pegs past full when it's not working properly, but decides to function sometimes? Loose wire that sometimes connects, perhaps? Mine is a '79

Sound like the sending unit wire (resistance wire) is loose some where. Check the tank. You might be able to reach in from the filler cap and giggle the wire and see the gage react. If it is not there you will have to follow the wire back to the gage.

 

[LorinD]

I have a '71 that read 3/4 tank , the problem was a bad fuel gauge .

 

[bill81vette]

AlanEla,Welcome to CAC!!!!
hope you enjoy the forums!!!!


stop by the new members section and introduce yourself!!!!

 

[jesus4sports1]

My 81 vette

[

My 81 vette has a problem with the fuel gauge bouncing. I had the sending unit replaced because I thought that was the issue, but it is still doing it. I took it back to the shop and they put a larger ground wire on it thinking that was causing part of the problem, but it is still bouncing. Can anyone point me in the right direction because I have already wasted money on a sending unit that didn't fix anything.

 

[Antz81]

[

My 81 vette has a problem with the fuel gauge bouncing. I had the sending unit replaced because I thought that was the issue, but it is still doing it. I took it back to the shop and they put a larger ground wire on it thinking that was causing part of the problem, but it is still bouncing. Can anyone point me in the right direction because I have already wasted money on a sending unit that didn't fix anything.

Aside from the bouncing does it roughly show the correct fuel level?

 

[jesus4sports1]

Aside from the bouncing does it roughly show the correct fuel level?

It does when it is sitting still but while driving it can bounce as much as a half a tank at a time.