Fuel Guage quit working
 

I have a 79 f-150, the gas guage seems to have quit working. I tried search but it has been disabled...

anyone have ideas?

Try manually searching the pages, this was covered about a week ago. Also try reading the sticky that says "Read First: 1973-1979: FAQ's, Tips & Tricks, Projects, and FORUM INFORMATION, -PLEASE READ!"

Could be the sending unit in the tank. It could be working electricly but the float may have a hole in it. This happened to me. The float is attached by a wire arm the raps around a brass "barrel". Mine wore out where they come in contact with each other. Believe it or not I wrapped electrical tape around it as a temp. fix and its still working about 2 1/2 years later.

https://www.ford-trucks.com/forums/1...uel-gauge.html

https://www.ford-trucks.com/forums/1...-1-2-mark.html

https://www.ford-trucks.com/forums/1...f-the-peg.html

Quick test to determine problem
 

Get under the truck and locate the wire that goes to the sending unit, unplug it and ground it out to the truck body. Make sure its a good ground. Turn on the ignition key. The fuel gauge should quickly rise to FULL. This tells you the gauge and wiring to the gauge is functional. You may also use an ohm meter to test the sending unit. Attach one end to a good ground and the other to the sending unit wire. No reading - bad unit. By bouncing the truck with fuel in the tank, if the unit is good you will see the meter reading fluxuate.

Thanks but I was a little vague last night...

The PO told me that one day the gauge lights on the left side of the cluster went out and the fuel gauge quit working.

The truck has dual tanks and it quit working for both tanks so I am pretty positive that it cant be the sending unit as both would have had to go out at exactly the same time.

The two sytems are unrelated.

Please NOTE: There is PLENTY of info in the links I posted earlier (post #4) to solve your fuel gauge problem.

Since you also have cluster light problems.
You need to pull the cluster and disassemble it and clean the printed circuit as the contacts get corroded .

see this pic.

https://www.ford-trucks.com/user_gal...id=139258&.jpg

Thanks guys...

rear tank, ground wire broken and aux tank had a badly corroded terminal... both work now.