Help with autometer fuel gauge

[dsapper]

I have a covan's dash inside my 72 camaro with the auto meter guages. The fuel guage worked great untill about a month ago. It showed completely empty when there was gas in the tank and about every 3rd time I drive it the guage shows full, way full all the way past the F and onto the needle stoping it.

Anyone know whats causing this?

[eldogg]

1st check your gauge and sender grounds, then I would pull the float out of the tank and move it manually. If the sender is old I have seen them act like what you are saying yours is doing.
Good luck,

[dsapper]

Another clue to what is wrong. Its not random that the gauge goes from empty to way over full, its when I turn my headlights on. I did it 3-4 times in a row, with the headlights off it goes all the way to empty, with them on its as far as it can swing (about 1" past full)

Does that narrow it down any?

[eldogg]

It sounds like the gauge is looking for a ground. Trace all of your wires and make sure you didnt make a mistake.

[matty b]

definitely a bad ground pull the dash down and make sure its screwed down completely, its a very common problem