gas gage 1977

[johnrem46]

My gas gage is spiked to the past full on the gage. When I start the car the needle move up about 1/8 of an inch. I looked for an open ground with no luck and now think the sending unit is bad. Is there any way of checking the sending unit without droping the tank? Or is there other things I can check to solve the problem. the gage is new the old one did the same thing.

 

[JohnZ]

Check out the attached tech column I wrote on C1 fuel gauge system diagnostics; the C3 system is exactly the same, except the resistance range of the sending unit is 0-90 ohms (vs. 0-30 ohms for C1's).