1930 cf gas gauge

[Mars]

I can’t get my previously working gauge to work. New wire from sender to gauge. And gauge to power. But it just pegs full. I’m baffled. Thanks 

[JACK M]

What happens when you take the wire off of the sender?

If nothing then try touching that wire to ground.

Edited April 8, 2021 by JACK M (see edit history)

[Mars]

At the sender or the gauge? 

[JACK M]

Take the wire from the sender, turn the ignition on, and see what the gauge does when you unhook it and then when you ground the sender wire. 

if the gauge runs opposite when the wire is grounded than when it is hooked up,  you may have a bad sender. Also if it goes opposite from when its hooked up to when its unhooked it is likely the sender.

If the sender is an open circuit it will make no difference when you take the wire off. If you complete the circuit by grounding that wire and the gauge goes opposite the it is the sender. Alternatively, if the sender has a short, the gauge will go to the opposite end when you unhook the wire.

Either way, if you can make the gauge move when you manipulate the sender wire it will be a bad sender.

I hope I did't confuse you. Tell me your results.

Edited April 10, 2021 by JACK M (see edit history)

[Mars]

Finally got it working, switched the wires on the gauge. Seems simple but I went by the schematic at first so I didn’t suspect that. It’s very jumpy. I don’t know if it’s the gauge or the sender.