Fuel Sender testing

[mpierce9]

Hello, i am trying to test my fuel sender before I do anything drastic. If the sender is working as expected and there is just a wiring issue I should be able to (using a ohm meter) attach a lead to the sending wire (tan wire), and one to a ground and read the resistance to get an idea of the fuel level correct (Based on this thread)?

Here's what I have done so far. First thing was to read several threads on here. I'm following their advice and would like confirmation of my next steps.

• Originally the fuel gauge read at 3:00 position. (Indicating an open circuit?)
• I grounded the sender wire from the gauge and got an Empty reading (as expected)
• This removed my focus from the gauge
• Identified the fuel tank sending unit ground wire and made sure it was attached to a clean verified ground (observed continuity between the black side of the battery to the ground wire for the fuel tank)
• Identified and test that the tan sending unit wire coming out of the fuel tank was not (contacting) grounding to the fuel tank (was unable to observe continuity between the fuel tank and the tan sending unit wire)

Here's where things fall apart.

After cleaning up the ground and re-verifying it to the black side of the battery.

I checked the resistance to ground of the tan wire near the fuel take it read around 200. I had my wife bounce the rear end of the truck and the reading went haywire and settled back around 200.

I then checked the tan wire inside the engine compartment, and it read 56. I still haven't read it once inside the cab or at the gauge. I dread taking the cluster out again.

The gauge went from the 3:00 position to about the 2:30 position and is currently holding steady there. . . . here is an image:


Any direction here would be great.