I have read a number of posts on related issues and am unclear if I have a bad DFR or weak fuel pump. Have 96 F250 4x4 w/ 460. Front tank when selected reads empty regardless of how much fuel is in it. When rear tank is selected fuel feeds into front tank. Truck runs fine on either tank (so long as you don't mind 11mpg at $3.90 gal).

Thoughts? THX in advance

 

I have the 1990 efi inline 6 with dual tanks and i had the same issue. Mine actually over flowed a few times before i caught it so be careful.

Turned out to be a bad check valve in the front tank fuel pump for the return line. I had to replace the pump as its all one assembly as yours should be as well.

For the gas gauge not reading the true level. you may have a bad sender unit or damaged wires on the back of the tank selector switch or anywhere in the line to the sender unit.

 

The check valve in your front fuel delivery module is stuck open so the module has to be changed. Sounds like the pump inside it still works so you may want to keep it as a spare, and while you're in there install a new fuel level sender.. it bolts to the outside of the FDM.

 

Great information guys, much appreciated. Now to get it on the lift and change it out.