Remove the sending unit so you can move the float up and down and use a good volt ohm meter to see how much ohms the sender has at the lowest and highest lift from the float, I'm thinking from 15 ohms to 30 or maybe it is 15 to 60 ohms, CRS scope
If it doesn't change you need a better sender scope
if it does change then follow the wires to where it doesn't change going to the gauge wrench up
Gas senders are wire wound variable resistors, also known as varistors, there is a lever on the float arm that rides against the wires to complete the circuit back to the gauge changing the resistance as they go up or down scope

Last edited by Cab_Burge; 07/14/22 01:37 AM.
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)