I purchased a new sending unit for the in cab fuel tank. It bench tests correctly. When I install it, it appears to not work. With the sending unit wire not attached and a full tank of gasoline I get the following. Continuity between the sending unit post and the tank-cab-negative side of the battery. I believe I should be getting about 28 ohms of resistance, just as I saw when I bench tested the new unit. I do not have a ground strap installed on the sending unit. The readings I am getting is that all the sending unit post and body are at the same potential as the truck frame and negative side of the battery. Perhaps I am missing something, it is odd to me that a unit bench tests correctly 0-30 ohms as I move the float up and down, but does not work when installed. The float works, I can see that when I place it in the tank.
