I have duel fuel tanks. When I switch to the rear tank nothing happens and the engine dies. The front tank with engine running reads empty, but when the engine is off w/the key off reads 1/4 tank regardless of how much fuel I have.
You'llhave to check to see if your switch is any good as well as the solenoid under the truck where the fuel lines connect. It could have a broken wire, or no power. This could also be the problem with the sending unit as they go through that as well.