I have a f250 xlt 4x4
Automatic 5.8
I bought the truck second hand and i ran into quite a few problems that i fixed
I have been running and filling gas from the back tank just fine, switched to front tank and always ran really rough.
Just this morning it switched on me and back tank runs rough and front tank good but when i press the gas it sounds like it chokes out and dies, start it up again and idles good but press gas again and dies.
I put gas and it only took in less than two gallons before it over flows.
Any help would be greatful

 

How long have you owned the truck? Did PO indicate he used both tanks regularly?

Sounds like you may have sucked up bad/dirty fuel from the front tank by switching it over those times.

You will want to check fuel pressure first thing, if pressure is good it may be an injector clogged.

The tanks certainly did not "switch" on you, as far as one being bad and the other good, now the front is good and back is bad. Switch back to the rear tank permanently, and begin your diagnosis from there. Once fixed and running smoothly, then work on the front tank and figure out if it's dirty and full of bad fuel.

 

Right but will tht stop me from putting fuel into either tank? If i put in either tan it dont even take in a gallon and i do know there is barely any gas in both tanks

 

I only owned the truck for four months

 

Are you talking about, while pumping gas at the station, the pump clicks off after only a few seconds of pumping? Try filling a gas can, and then dumping that in manually.

Does your trucks fuel guage work?

 

Everything works great on my truck and i did try with my own gas can...noticed gas came out tthe back tank while putting gas in front tank and vice versa

 

You are saying that when you put gas in the front tank, it spills out of the rear tank fill tube? And when you put gas in the rear tank, it spills out of the front tank fill tube? Am I understanding you correctly?

 

I am not extremely familiar with dual tank setups, but AFAIK the two tanks should not interconnect in a way that would allow that... IE, one could be full while the other is completely dry... they should not siphon into each other, but I may be wrong. Maybe someone with more dual tank knowledge can chime in here

EDIT: Doing a quick search turned up what sounds like a similar issue. may want to read this: https://www.ford-trucks.com/forums/1...-problems.html

 

First off, we need to know the year of the truck, there are 3 different 2 tank systems.


Second, when you say there is barely any fuel in the tank, that could mean there is barely enough fuel for the pump to pick up. OR there is water in the tank. cold be from condensation, or a fill up that was contaminated . Filling with 5 gal cans will put water in a tank.

Third, if the fuel will only go in slowly, it could be that your vapor hose is removed, or has fallen off the fill tube, and the vapor can not get out as the fuel comes in.

Forth, Tanks pumping from one tank to the other is another problem, cause by a bad check valve. Those tanks are from 92-96.

 

Another simple solution is someone has dropped the tank previously, either you or the PO, and when they put the filler hose back on they didn't do it right. Srewing up the flow of fuel. It may seem like the tank is "filling" when in reality it is only the filler hose overflowing. I had this problem on my 95 F250. Also Fuel filters may be clogged and need replacing.

 

Its a 1992

 

92 has a FDM ( fuel delivery module). If the pump is running, and your fuel pressure is incorrect, The problem could be
1 fuel filter
2 sock( screen) on pick up , at the bottom of the pump is clogged
3. water in tank
4 fuel level too low for pump to pick up

The cross flow problem was a 1992 recall, since abandoned, but basically, The fuel system runs a common fuel line for pressure, and a common line for return to both tanks.

What occurs, the fuel pressure regulator gives up, and supplies full pressure to the check valve on the FDM's in both tanks. Eventually the check valve fails, allowing the return line to fill which ever tank is easiest to fill, no matter which tank is pumping.

Ford's cure was to replace the Regulator with a carbon steel regulator, and place a check valve in the return line at the fuel tanks.

Your cure will be to replace the regulator, and replace the FDM on the tank that is getting filled.

You may get lucky in some junk yard search and find the Ford check valve, But There are very few left.Your talking about a 20 year old truck

I hope this has been some help for you.

 

Will that problem cause the fuel to come out on top the tank? I was just wondering because the fuel is coming out now somewhere around the tank, maybe on the top

 

Yes it will. You can't put 20 gals in a 19 gal tank.