Help! I need some of it for a stubborn gas gauge. Both the gas gauge and the temp gauge on my 65 Custom cab had their needle go all the way to the right upon turning the key; I replaced the instrument panel voltage regulator, and this fixed the temp gauge, but not the gas gauge. I even replaced the gauge itself, but to no avail. The gauge does rock back and forth when the tank is half full and I take a "hard" turn, and seems to be "empty" when reading 1/2 full. Thanks for any advice.

 

When you had that spike on the guages, it may have fried the gas tank unit. A simple test is to take the wire off the tank unit and ground it quickly with the key in the "on" position. It should go all the way to full. If not, the guage is bad. If it does, the tank unit has problems. There's a certain ohms rating it falls into when it is in the various positions. I think if you do a search on this subject in the archives section, the posts on that subject will tell you what they are. I remember seeing them posted, but can't remember how far back (CRS).

Barry

 

Not an authority on topic. Not too long ago, installed instrument cluster and came across section in manual found helpful. Another test for the fuel gauge is to turn off ignition, connect terminals of two series-connected flashlight batteries to the gauge terminals in questions, fuel, oil, temp. The three volts of the batteries should cause the gauge to read approx. full scale. If gauge is inaccurate or does not indicate, replace. If the guage unit is still erratic in its operation, the sender unit, or wire to the sender unit is defective. I took top off flashlight battery and place one lead from gauge terminal to the positive post on flashlight battery and the other lead from gauge terminal to the flashlight on/off button with button in on position, negative side of battery. barry has already mentioned the test at the tank. Suggest check ground wire at tank make sure clean and secure. If you find yourself working on the electrical system with any regularity, suggest purchasing wiring diag., reasonably priced thru Motorhaven; in addition to an olm, volt, and continuity tester if you do not have one.

dave