Fuel gauge troubleshoot


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Jul 17, 2021
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Going to troubleshoot the fuel gauge in my 1970 300 that’s not working.
I’m going to ensure I have a good ground between the sending unit and the steel fuel line first.
Someone in the past told me that if you disconnect the wire from the sending unit, and connect it to ground, and then quickly turn the key on and off. If the fuel gauge needle goes up then that tells you that everything is good to the sending unit.

Does that make sense to you guys here, or is there a better way to troubleshoot the fuel gauge?
Normally that should work to tell you if the gauge is working. You may have to leave the key on for a few seconds to see if the gauge will react.
Is the ground strap still in place? There should be a narrow metal strap with clips on each end. One end goes on the metal sending unit output line and the other goes onto the metal fuel line after the fuel rubber hose that connects the sending unit to the metal fuel line. They commonly rust and fall off. Two small clamps and a piece of wire will work.
Yeah Fury, first thing I always check.
This car has the wire with 2 clamps, but that doesn’t mean the wire is grounded to tge pipe so I will ensure a good ground first and then go from there.