I have a 97 F250 460 gas truck with duel fuel tanks I will not run on the front tank but when you move the dash switch to the front tank the gauge works but the fuel pump will not run even if you cycle the key to the on position. Also I noticed that it seems that fuel is being pumped to the front tank when I am running on the rear tank. I can remove fuel from the front tank and after driving for a few miles there is gas comming out of the front tank gas cap and there is pressure when removing the cap. Is there a selector switch for this system or is the front fuel module gone bad?

 

Please I need help with this Thanks

 

i would say its your switching valve, my 85 mud truck did this but since i blew a hole in the side tank i just removed all the extra lines for the side tank and ran only the rear tank

 

Moved to the 1987 - 1996 F150 & Larger F-Series Trucks forum.

 

I didn,t know they used a selector valve in 97?

 

I had the same exact problem on my 96 F-250 7.5L, i think all the gasoline fuel systems are the same. In those years, there is NOT a fuel selector valve. When the fuel pump goes bad, your engine will have hard times starting on the bad tank. So you naturally use the good tank, but the bad pump allows fuel to enter and since you aren't using it, the tank gets full and spills over. Do yourself a favor and change both pumps, not just one. I thought that since one pump is good just change the bad one out, but the new one will be too strong and you'll end up having to replace it too.

 

Yes the front module is bad.
There will not be any more pressure with a new pump/module then the old one so no need to change the rear module.
The pressure is regulated by the fuel pressure regulator on the engine fuel rail.

 

I was told to change the fuel pumps both at the same time. I'm a believer too because my second "good" pump went bad shortly after changing out the first pump. Why are you calling it a module, it's a fuel pump. The pumps put out however much fuel pressure as they come from the factory (I'm guessing 40 psi) all the way to the regulator on the engine, the excess fuel is routed back to the tank. Do yourself a favor and change both fuel pumps.

 

The pumps putout around 100 PSI into a closed head.
It is called a module because that is what it is.
When you change out the module you change out the fuel pump at the same time.

The fuel delivery module (FDM):


The fuel system:


/

 

On gas EFI engines w/ dual tanks there is a fuel pump in each tank and a selector valve on the frame rail in front of the front tank, that both tanks run into.

When the system is working correctly and the dash switch is set on the front tank the front tank fuel pump is energized, the fuel flows through the selector valve to the engine, the unused fuel is returned from the engine through the selector valve and then returned to the front tank.

When the dash switch is set on the rear tank the rear tank fuel pump is energized, the fuel flows through the selector valve to the engine, the unused fuel is returned from the engine through the selector valve and then returned to the rear tank.

So, you have two issues. FIRST: Your front fuel pump doesn't work (per your original post). SECOND: Your selector valve has gone bad (that is why the fuel from the rear tank is returning to the front tank).

Not a problem to fix just time & $ as usual. I'd remove the bed from the truck so you will have easy access to everything from the top. (That's how they were built from the factory the bed went on last.) Replace both fuel pumps w/ new so you don't have to do it again because you only replaced one or the reman pumps go bad while "covered under warranty". Replace your selector valve at the same time, and throughly check your fuel lines for wear & tear and replace as necessary. It's a nice weekend project w/ at least 2 friends helping you pull & install the bed. Good luck.

 

NONE OF THIS IS TRUE.
You are very, very wrong about how the system works.
There is no selector valve in a gas FI truck in 1997 That is OBD-I.

 

OK, sorry, but this is exactly how my 1993 OBS 5.0L F-150 was when I replaced all these parts in 2002.

 

i'm almost 100% certain there is NO fuel selector valve on the rail for two reasons: #1 my tank stopped filling up with gas when i installed a new pump, #2 i took the bed off and looked for a fuel selector valve and didn't see one, #3 I know what a fuel selector valve looks like because i own an 84 F-150 and changed one out. If you guys are so smart, why don't you guys help me out with my problem? "96 F-250 speedometer and engine stalling"

 

93 is different from 96, the newer trucks don't have a switching valve or fuel reservoir.

 

Good Luck J and J.
I'm out jdcrew.