Had this tiny problem, went on a weekend trip, 300 one way. Got close to my destination and needed fuel, late at night few options so I put in 10 gallons at a 7-11. Went to hotel then bed. 6 next morning on the road again, 10 miles out truck shuts down, called a friend and we flat towed it to his place. He called a friend of a friend who knew a guy who had a scanner to pull codes. 0087 low fuel preasure. So we pulled the filters. Primary was stained but not what I would call plugged. Secondary stained. No water, rust or metal any where. Tried to bleed but could not seem to get air all out. set fire to the truck and called insurance man. Not really just a joke, but tells where my mind is at. Rented a car and came home. Went back this Saturday with the trusty 7.3 and a gooseneck to brink it home. I did however take along a Bosch 1300 scanner to pull codes. and got iirc 2290
low fuel rail preasure. but not 0087. also had truck immobilized theft detected. Cleared those re bled fuel lot of air at Schrader so I cracked the banjo bolt at the cooler and got mass quantities of air there. tried to start but just spins. Re cracked the banjo and more air. More air at schrader
Fork it loaded it up and hauled it home. low rail preasure code is back,
so here is my Question. The kid who had the first scanner went to town and came back with Purolator filters that we installed the first day. Is it possible that those filters are just unsuitable and will never bleed out? the air that I can't seem to expel be causing the low rail preasure. There is another code for incomplete something or other that code connect says I need to drive to clear. Could that be the problem. Can't believe it is the hpfp. Don't know how they fail though. This thing just died. Like if I cut off the key. No noise no buck no nuthin. Helpful insght welcome.

 

Not going to say the purolator filters are the problem, but aftermarket filters have caused issues. I use nothing but Motorcraft. Air in the fuel system will certainly cause low pressure. How much fuel is in the tank? You might have blockage in the tank too.

 

Get OEM filters on it. Recharge the batteries and purge it good.


Key on, listen till the buzz stops. Key off. Repeat 8 times.


OEM fits, others don't.


Also ensure the caps are on completely.

 

Forgot to mention that. The 6.4's are the worst for getting the air out of the fuel system! (are the 6.7's just as bad?)

 

Thanks fellas. I bought Motorcraft filters Sunday not got that far yet. Off on Wedensday. Will get them on and start from scratch. I have dual tanks so I will dump clean fuel into the back tank and work from there. I haven't heard of these trucks fuel pickups breaking, but I suppose it is possible there is a crack on the pick up. I have inspected the fuel lines for signs of leaks visually but I suppose they could be sucking air and not sow signs of fuel loss. How about a vacuum pump with a catch tank on it to pull the air out?
It appears that the fuel return goes to the cooler and then goes to the filter again. So my thought is if I pull Vacuum on the Schrader port I should pull air from all parts of the system. Thoughts?

 

Senix, We did the Ford guided fuel purge at least 80 times still getting air. May even jumper power to the lift pump and run ten gallons through if I have to.

 

After putting on correct filters, then purge and before starting check the fuel cutoff switch and see if it is tripped.

 

Camp, Without a definitive way to measure flow except that it seems like it is enough, a blockage in the tank is probably not the issue. I bet this thing is moving a couple of quarts per key cycle. ie 2 qt. per 30 sec. I can surly measure that with a mason jar and a stopwatch. May just do that.

 

We did check the cutoff last Saturday. Correct me If I am wrong but, the cutoff interrupts power to the lift pump, and should throw a code saying it is tripped. Yes?
But will Do again. I miss the simple days. When I get home tonight I am putting glow plugs in my old 6.9. that is one damn fine engine. Slow and steady but key word steady. I bought this 550 to give that old girl a retirement of sorts but I guess I need to press her back into service. Just old and slow like me.

 

The fuel system is suppose to purge the air through the return line. I would not try to pull a vacuum on it.

Since it has dual tanks, you might want to inspect the valve that switches between the tanks.

 

Good point. If no check valve on the return I could feasibly draw direct from the tank through the return. I have visually looked it over but again no sign of fuel weeping like the push-on connectors on the rest of the system. Truck is amazingly clean underneath. Would be real easy to spot a leak to atmosphere.
Any guidance on inspection other than visual? Can it be disassembled and re-packed (sealed)?

 

With someone flipping the switch, try to listen and feel (put hand on valve) to see if it sounds like it is switching like it's suppose to. I had a 97 that I would sometimes have to stop and hit it to make it switch.

 

Roger. Could be dash says front, valve stays rear, rear tank mostly dry suck up a bunch of air truck dies. Very real possibility. I had a 97 as well 350k mileage when I sold it. The 02 has 200k on it now. no telling what the 85 has on it. I venture a lot.

 

My 97 was falling apart around the motor. 392,000 on it when I got rid of it. The motor I would've trusted for a long time.

I think you've located the potential problem!

 

Lets hope so took all my money and then some to buy the truck.