73 Road Runner Gas Gauge Problems

[crazy440car]

I am wondering if anyone has had this problem and could help me work through it. My gas gauge stopped working. So I replaced the sending unit, the instrument cluster volt regulator, the instrument circut board, and the gauge itself. I am pulling my hair out....anyone with suggestions would help greatly.

 

[luther]

I had a fuel gauge problem in my 73 Rd Runner, but replacing the tank sending unit fixed it. Have you checked the wire from the sending unit up to the dash? On my car, it's a dark blue wire. Mine is the "plain-Jane" version, with no tach and only the simple dash. But that wire is probably the same color all the way to your printed circuit connector. It might help to clean the contacts in the connectors along the way to that PC connector (should be another one in that path with 6 pins in it). I've used contact cleaner/lube on every electrical connector I've had apart.

Good luck, Luther

 

[crazy440car]

I actually replaced the wire as well

 

[luther]

Hmmm. I would make sure power is getting to that circuit. If the sending unit wire has continuity all the way to the gauge, then I would check for voltage getting to the other pin on the gauge.

 

[Ron 73]

Id add that you should be sure of your grounds, Ive had a lot of problems in the past and surprised at just how many lead me to a bad ground or corroded plug in (my sending unit plug).

 

[tpodwdog]

ground out the sending unit wire to a good ground. if the gauge peaks...you know the wire is good...if it does not peak....2 things,,,,either the wire is faulty( check connections)....or ....no power is getting to the sending unit .( check your FUSES). also , make sure there is a ground "jumper" from the sending unit to the fuel line. it jumps the little piece of rubber hose near the sending unit on the fuel line

are the other gauges working? .....

 

[crazy440car]

I added a ground wire to the back of the actual gauge and the gauge moves up to the 1/4 mark but I have a full tank. The temp gauge doesn't work at all?????

 

[luther]

Sounds like multiple problems to me. The wire from the sending unit must not be making good connection, or you would at least get !/4 reading if it was. With the temp gauge not working either, check the path getting battery voltage to the circuit board. Connections appear to be bad for paths getting to both sides of the fuel gauge.