'66: Fuel gauge not working...

[bandit2]

The fuel gauge is not working. It was working fine until the body restoration, but hasn't worked since. Any ideas how to fix?

 

[krash kendall]

Check the plug on the sending unit, they come off quite easily. The constant voltage unit on the back of the dash may not be functioning (the temp guage won't work either).

 

[bandit2]

The temp gauge works.

 

[ForceFed70]

Could be the wire to the sending unit or ground.

Take a digital multimeter and measure the resistance between the fuel sender/pickup plate (under the tank) and the frame. The resistance should be really low. If it's not, then the pickup isn't properly grounded.

 

[dennis112]

Unplug the wire from the sending unit and ground its (the wire's) conductor to the car chassis--it won't hurt anything. The gas guage should peg when grounded and be on E when it is not.

If it pegs, concentrate your efforts on the sending unit. If the guage doesn't peg, then concentrate your efforts on the guage and the wiring.

 

[iskwezm]

mine did this too after the guage overlays,but ive been to lazy to mess with it,so i just put in 15 bucks every time i drive it

 

[snowball]

mine did this too after the guage overlays,but ive been to lazy to mess with it,so i just put in 15 bucks every time i drive it

I wish it would only cost me $15.00 to top up my tank.

While I don't wish to hi-jack this thread, my fuel guage is not reading correctly. When the tank is full, the guage only goes up to the 3/4 full mark. When empty, or as close to empty as I'm game to go, the guage is still reading 1/4 full. Any suggestions as to the cause?

 

[66stangbluework]

mine does the same thing snowball

 

[iskwezm]

I wish it would only cost me $15.00 to top up my tank.

While I don't wish to hi-jack this thread, my fuel guage is not reading correctly. When the tank is full, the guage only goes up to the 3/4 full mark. When empty, or as close to empty as I'm game to go, the guage is still reading 1/4 full. Any suggestions as to the cause?

Who said i top it off? thats only about 5 gallons

 

[snowball]

Who said i top it off? thats only about 5 gallons

That'd be great. $1.30 a litre down here. That's over $5.00 a gallon in your terms.

 

[bandit2]

I grounded the sending unit wire and the gauge went to full. When the SUW was not grounded, the gauge remained at empty. After I reconnected the SUW to the tank, the gauge went from Empty to 1/4 full. I know the tank is about 3/4 full... so that reading is not accurate. So the problem is the sending unit?

 

[tos]

I grounded the sending unit wire and the gauge went to full. When the SUW was not grounded, the gauge remained at empty. After I reconnected the SUW to the tank, the gauge went from Empty to 1/4 full. I know the tank is about 3/4 full... so that reading is not accurate. So the problem is the sending unit?

You could be grounded but maybe not a good ground. Those sending units are just big reostats and depending on their position they send different volt readings to your gauge(Actually they are completing the ground in that circuit). A half a$$ ground will send a lower volt reading resulting in a lower level reading. So they have to be grounded to the tank good and the tank has to be grounded good and the ground strap from your engine to body has to be good etc...Ground, Ground, Its always a ground problem.

 

[Kriek]

Thank you! I was about to replace my sending unit before I read this thread. 5 minutes redoing all the grounds and the gauge is dead on accurate now. This ironically isn’t the first time a poor ground has caused me problems.

Thanks again.

- Jon