thanks for any help in advance! i have a 96 F350 7.3l 5 speed, it has the dual tanks. last week i put deisel in my back tank which i dont usually use because it has a small leak, when i went to switch the fuel tanks on my dash i noticed the gauge went way past full so i switched it back and forth a couple times from front to back. i left it on the back tank and gauge still was past full, i drove down the street a couple miles turned truck off and when i started back up less than a mile down the road it acted like it ran out of deisel. i havent got it to start since. i checked fuses they seem to be good. i drained the fuel bowl and added fresh deisel still wont start. i noticed a little bit of air release when i drained the bowl. i tried starting with the fuel filter off to see if deisel was entering bowl and didnt see any. yesterday i put jumper cables on the truck thinking it was the battieres and sometimes the truck acted like it wanted to start but didnt, i also got white smoke while doing this which i didnt previous days. Any suggestions on what i should try?? Need truck running ASAP.

 

switch to the front tank for now. hopefully there wasnt any "junk" in the rear one which sounds like there was. also sounds like your not getting any fuel because is sounds like its plugged somewhere. it could be multiple things. where is the hole/leak located in the tank??? is the engine turning over???

 

yes the engine is turning over. when i switch to the front tank the needle doesnt move it stays past full, when i know i have about 10 gallons in there. The back tank has a leak on the bottom from the rubber underneath wearing and the tank rubbing metal to metal.

 

Check the fuel pressure at the schrader vale on the fuel bowl. You can use a cheap pencil type tire gauge for this. You should get at least 20 lbs. while cranking. My guess is if the rear tank hasen't been used in a while, the tank selector valve is sticking, and not allowing fuel to draw from the rear tank. Switch back to the front tank, after adding a little fuel to it.

 

You probably won't see fuel pumping into the bowl when you remove the filter, because IIRC there's a mechanism that cuts it off when you remove the cap and/or the filter. You can check fuel pressure by putting a cheap stick tire gauge on the schrader valve on the regulator while an assistant cranks the engine.

With the key in RUN, do you hear the selector switching tanks when you throw the switch? The selector not only opens/closes the right valves, it switches the feed for the gauge. So if the gauge worked properly on the front tank before, but is now not working on either tank, it's quite possible that it's stuck between the two positions. So the fuel isn't feeding from (or returning to) either tank, and the gauge feed is not connected to either sender, so showing infinite resistance (which pegs the needle past full).

 

Get a charger on those batteries too.

 

Check the HPOP reservoir, it has to have oil near to the top (about 1/2 inch IIRC).
Are you sure that the fuses are OK?

 

My truck acted like it ran out of fuel like that and wouldn't start back and had similar symptoms and all it ended up being was the cam sensor went bad...

 

Welcome a board. Yes de CPS makes a lot of weird things.

 

it ended up being the fuel tank selector valve when i took off the suction line it released all the air from trying to start it. all i did was bypass the valve to only the front tank since the back one is leaking a little bit. my fuel gauge is still laid down past full, is there anyway to fix this problem without having the FSV??

 

BTW there are not any pump in the tank.

End the winner is (are)...........

Glad you fixed it, and thanks for the update

 

Pegged fuel gauge means an OPEN circuit (infinite resistance). When you bypassed the selector, what did you do with the gauge feed (which is switched by the selector)?

 

Have you checked the in cab fuse panel for a blowen fuse? Fuse #6 controles the fuel selector, which also controles the fuel gauge. It is a 15 amp fuse (blue).

 

yeah sorry, had a brain fart. was thinking gas.

 

Here's the wiring diagram (argh, dunno why FTE makes it so small):

Did you physically remove the valve? Or is it electrically disconnected? If so, looks like you can put a jumper between terminals 4 and 5 on the connector (yellow/white and dark blue/yellow) and the front sender will feed the gauge.