Van_a_Rockin

Is there a method of determining the valve that switches between fuel tanks on a 91 E150 Econoline W/ 5.0 FE, is functioning properly.
Currently, I only run on the rear tank, when I flip to the front tank, the fuel gauge cuts to enpty as if engines off. I've tried running on it anyway, assuming the gauge was faulty, but not sure how much fuel was in it, I switched back, only to learn it was drawing fuel from the rear all along. WTF?

Any advise would be hightly appreciated.

Van_a_Rockin

Was told there are separate fuel pumps for each tank.

If this is true, and the switch tests ok, then maybe the secondary fuel pump for that tank be dead?

If so, would I need to drop the #!@! tank to get to it?