Hey everyone, thanks for taking the time to read my post.

So about 2 weeks ago my truck started dying out when switched to the rear fuel tank. I figured the fuel pump must be going out, so I've been only using the front tank.
Well a few days ago the truck started randomly dying on me while driving - no check engine light, only the red battery light would come on. It starts right back up, so I would just stay in the slow lane in case I needed to pull over. Well today it's been dying all over the place. At stop lights, on the highway, etc. (both tanks are full)

Also, today I noticed that there was a lot of gas residue around the rear fuel door, which I haven't touched since I filled it 2 weeks ago, so I thought that was odd. To my surprise, when I popped the rear cap, fuel started gushing out (at least 2 gallons). Then I popped the front, and it was pressurized, like opening a bottle of soda. I figured it was something to do with the rear pump, so I picked one up on my way home. However, after reading a lot of forum posts, I'm not so sure this is my issue. I've read a few posts which are kind of similar, but not really - So I'm hoping some one will have some insight for me.

I purchased this truck from a co-worker who is really **** about his things so I know he took really good care of this truck - because besides this issue it's a peach - even with 250,000+ miles on it. Any and all help is appreciated. Still waiting to hear back from him about the recall i've read about, to see if he ever replaced the fuel pressure sensor.

EDIT - this is the recall I was reading about
Component: FUEL:FUEL TANK ASSEMBLY
Manufacturer: FORD MOTOR COMPANY
Potential Number of Units Affected: 275000

Vehicle Description: Light duty trucks and cab chassis equipped with gasoline engines and dual fuel tanks. The carbon steel fuel pressure regulator in the fuel system can wear out during the life of the vehicle. If the fuel pressure regulator malfunctions, it can cause high fuel system pressure, which damages the fuel pump check valve. This allows fuel to be transferred from one tank to the other, possibly overfilling the non-operating tank, resulting in fuel overflow past the filler cap.

Fuel leakage in the presence of an ignition source could result in a vehicle fire.

Dealers will have a stainless steel fuel pressure regulator installed. Owner notification began July 9, 2001. Owners who take their vehicles to an authorized dealer on an agreed upon service date and do not receive the free remedy within a reasonable time should contact Ford at 1-866-436-7332. Also contact the National Highway Traffic Safety Administration's Auto Safety Hotline at 1-888-DASH-2-DOT (1-888-327-4236). (See previous NHTSA recall 93V-125/Ford recall 93S68

 

I am almost sure that recall was for 1990 - 1993 trucks. The issue you are describing is all too common on this vintage truck and has nothing to do with the fuel pressure regulator.

The issue is called cross-flow and is usually caused by a faulty check valve in the tank that is being filled.


courtesy of Subford

Ford did have another recall for this issue but it was a band-aid fix (in-line check valves) that in many cases did not work. The only sure way to resolve the issue is replacing the offending Fuel Delivery Module. In your case that would be the rear one.

More threads on the same issues: https://www.ford-trucks.com/forums/s...rchid=13801670

 

So I should go ahead and replace the fuel pump? Am I correct that the bed needs to be removed to replace the pump? Also, do you think I should replace both of the pumps?

 

It is highly suggested to replace the entire Fuel Delivery Module, not all replacement fuel pumps have the check valve. It's pricey.....

Whether or not you want to do the front depends on several factors. The front pump pressure is probably being diverted to the rear tank, hence the reason for the stalling. You might want to check the fuel pressure by renting a gauge. It is rare for both Fuel Delivery Module check valves to go out but not impossible.

No, it is not a requirement to remove the bed to replace a pump/FDM. I have been successful dropping the tank from underneath. I used two nylon straps and a floor jack, worked like a charm.

 

I def owe you a beer sir. I'll be replacing this today, I'll post back with results. thanks for the help!