hey guys, asking this for a friend. i am not very familiar with the 6.0.

he has an 05 F350 dually 4X4. it was running fine, then died like it ran out of fuel.
towed it home, and it would start and idle, but when put in gear it would fall flat on it face and sound like it was only running on 4 cylinders.
life got in the way and it sat for a while. now trying to get it going it does the same thing.
i went over today to put autoengenuity on it, and it ran out of fuel.
before i got there they had already bypassed the fuel tank and had it hooked up to a can because the pickup in the tank is bad.
anyhoo, got more fuel and fired it up. it sounded like a bad under valve cover harness.
after doing some tests, we came up empty.
he pulled the fuel filter and it was empty. we cranked it over and the fuel into the filter was full of air.
so it seems like the fuel pump is bad.

would a bad fuel pump pumping air bubbles into the filter be enough to cause the engine to not rum properly. or loose cylinders?

 

Did anyone pull the filter down in the HFCM? That is the pump, down under the driver on the frame rail.
Yes, a weak HFCM will make things run like crap, and 6.0 injectors get really cranky when starved for fuel, don't run it that way too long.
Low fuel pressure and a failing FICM are a 6.0 injectors worst enemy. With the upper fuel filter cap off, and the filter out, have someone turn the key. The bowl should fill up within a second or two.

 

the filter bowl fills rite up, but the fuel is full of bubbles. when it was cold today before i got there it started and ran perfect. high idle even worked. but once it warmed up it started to sound like it was loosing cylinders, then ran out of fuel as per his father who called to tell me that a few minutes ago.
once we put fuel back to it it would not run on all 8.
that is why i thing the fuel pump is failing and pushing air.
these trucks have rotary fuel pumps in them, rite?

 

Just because you said you weren't familiar with the 6.0 I'll break it down a little. Hope I'm not telling you stuff you already know.

These engines have a HEUI fuel injection system which is a hydraulic over electric set-up. It has electrically operated spool valves that operate the injector but they are much to small and weak to squirt the fuel with the pressure it needs for a high compression diesel. The hydraulic part is doing the work, it consists of a high pressure pump that pulls oil from the crankcase, the injectors, a Injector pressure regulator (IPR), a sensor to monitor the pressure (ICP), an oil cooler plumbed into the coolant system and some wild plumbing to connect all these parts together.

Before replacing the fuel pump, hook up your AutoEngenuity and watch both ICP and IPR.
ICP has an operating range of 0-4,000psi and varies as rpm and engine load changes. It is directly reading the pressure in the high pressure oil system. IPR has an operating range of 0-85%. 0 is relaxed, fully open and making the least pressure, 85 is closed as far as it will go and making the most pressure possible.

What you're looking for is that magic 500psi while cranking, that's the minimum necessary for the engine to start. While keeping one eye on that, watch how far the IPR is having to close to get there. It's common to for it to jump up while cranking but if it's rock steady at 83-84 and it won't make 500psi, either there is no oil getting to the system, the pump is bad, or (most likely) there is a big leak in the system.

It's common with a leak for it to crank when cold because the oil is thicker and then die or fail to start when warmed up and the oil is thinner.

All the parts of the high pressure oil system including the plumbing are inside the engine, a leak runs back into the oil pan, you won't see it on the outside of the engine.

A couple other things to check are the fuel injection control module (FICM) voltages AE will show you those. Main power should stay above 45v at all times, VPWR should be battery volts or close to it and FICM sync must be a 1 (yes) before it will squirt the injectors.

With extended cranking you may see Sync fail or stick as 0 (no). This is common with a lot of cranking on a no start truck, this Sync is related to the cam and crankshaft position sensors and is seperate from FICM Sync. It also must change to 1 before it will fire up.

Check those out and post back and we'll try and help further.

 

when i said i know nothing about the 6.0, i should have said i know just enough about them to know i don't know enough to do much with them. i know the 7.3's, so i am familiar with the hpop system.

the problem is not with the oil system, it is in the fuel system somewhere. it starts rite up. it just would not run on all 8 when i was there. it almost sounded like bad under valve cover harness.
the thing that has me wondering if the fuel pump is bad is the aerated fuel into the fuel bowl. the tank was taken out of the equation by connecting the intake of the fuel pump directly to a 5 gallon fuel can and it still aerates the fuel into the fuel bowl.

 

I suppose you can call it a rotary pump of sorts yes, does not change the fact you need to pull the bottom filter and check it, along with the water drain......that thing might be full of crud.
IIRC it's a 35mm socket(bottom filter cap), same as the oil filter cap.

 

EVERYTHING about this Post SCREAMS Low fuel press Killed his Injectors


its going to be spendy lesson cause I suspect his low fuel thing went on for awhile having a Bad fuel Pickup tube


tell him to fix the Fuel pickup and slam 8 injectors at it FORD OEM Injectors ONLY

 

I suppose anythings possible fix the Fuel aeration first then see if any inject fail compression test


there are multiple points where fuel system could be aerated you need to do Separate tests to determine bad fuel pickup and to see if compression gas is forced thru the pintal of inject itself


anyway you look at it he hurt injectors so its a reliability thing

 

Sounds like the guys have the info , I would make sure your not pulling air in via HFCM the o- ring can get fouled up not getting a good seal, also make sure he's running a OEM fuel filters for both filters( no aftermarket) , the pick up needs attention low fuel pressure or no fuel when needed will knock out those injects , also on the upper fuel bowl check for leaks around where the blue spring goes , the key shaped gasket in the cover will leak sending air in.
Happy Thanks giving all