Camping at lake couple hundred miles from home. Truck pulled the RV great to the lake on Thursday.

Friday morning I get up to go get boat from dry storage; truck starts right up and then dies as soon as I put it in drive. Got the wrench icon. Restarts right up and I head off to get boat. Left engine running while hitching trailer at boat storage; go to gas station for gasoline for boat and air for trailer tires. I shut it off at the gas station while waiting for super slow guy in front of me; starts fine. Back to the campsite, shut it off, get our stuff in boat and go launch boat. Several hours later, she starts fine to get the boat back on trailer.

Saturday morning, we all load up in the boat. My son-in-law starts my truck and it dies; did this several times, then it would not even start and die. Getting the wrench icon. I try calling the local Ford Dealer to have it towed in; but, no service department on Saturday. We unhitch the trailer and roll the truck down hill out of way and hitch boat to his truck. Later that afternoon try to start it again; would sometimes start but just die. I drain fuel separator and get nothing but fuel. I have AutoEnginuity but didn't have it installed on new laptop; I manage to get it installed and check for codes. I have P2291 which is low injection rail pressure while cranking. I want to check pressure but all I can find is the volts from the pressure sensor; so I want to see what it is while cranking so I try to start it and it starts up; but I wasn't reading the sensor.....

Finally get it reading and I have 1.2 volts which from service manual is normal for idle and about 5,000 psi. I move the truck back to my fifth wheel and hope it starts in the morning (Sunday morning). It did and the truck ran just great with plenty of power and pulled the RV great. I've tried starting a couple of times since getting home. okay.

Searching the forums I come across an old thread that I had forgotten about until I read it again; I think it fits my situation as the truck was on a slight incline with the left front lower than the rest of the truck.

https://www.ford-trucks.com/forums/9...ink-about.html

When I get back from a trip (be out of town a couple of days) I'll try to duplicate the low left front corner of truck and see what happens; and if duplicated I'll print the above thread and take it to the dealer; and, I guess I'll owe Vloney for sharing.....

Fuel filters have just over 3K on them. Truck has about 63K miles.

Bob

 

Be aware of the valve 2-3 inches above the fuel pickup screen. If the fuel level is low and the valve is defective, that can cause a no start at an incline as well.

 

Dash was showing just above 1/4 tank; but PID was just under 25% for fuel level. Would that be low enough?

Currently it is about the same level as yesterday as it was full prior to trip to lake; and I filled it again before returning from the lake.

Bob

 

Still have any 36/36 warranty left? If so I'd take it in.

If not then consider taking a look at the tank.

 

Truck has +63,000 miles; so no bumper to bumper remaining. Took just over 28 gallons to fill tank after it started and I went about 8-10 miles from campground to fuel station; getting just less than 9 MPG so probably burned at least a gallon getting to the station; I would estimate there must have been at least 10 gallons of fuel in my 37 gallon tank.

I don't know if that would be above the valve Vloney mentioned. Sad thing is I 'harpooned' both my 04 and 06 and never took the time to really look at the details of the fuel sender or pickup. Guess I was more concerned with not getting any dirt on them at the time. I also tried looking in the manual for a illustration or something and never found one; maybe I was looking in the wrong place. Not doubting or anything was just trying to better understand.

Since I am on the return leg of the same trip with fill-up prior to each I am at about the same fuel level. When I get back in town (I am on a job related trip right now) I am going to take it to our rural property where I have some sloped ground to play with and park it with the front left lower and see if it starts the next day; if not I'll add diesel fuel (and use the tractor if necessary to pull it to level ground) and get it started.

I'll then go fill the tank and repeat the test.

Bob

 

I too have been getting the P2291 code. No related drivability concerns yet though. Not sure why I am getting the code.

 

No issues starting truck this morning, drove to work. Planned to drive to rural property for test after work. Got off of work and truck started right up and died; did this a couple of times more. I then cycled the key as one does after changing fuel filter about 8 times; cranked and she started.

I then went and filler her up with ULSD. Based on fuel purchased there would have been 10.3 gallons in tank. Dash indicated just under 1/4 tank.

Truck was parked on level pavement; I think I will drive it and see if any problems with full tank.

Would think the key 'on' procedure would not purge air if high pressure side of fuel injection; makes me wonder if issue is not on the low side and the valve in tank that was mentioned by Vloney.

Bob

 

I take it you have no starting issues. Have you changed fuel filters recently and possibly had a long crank to start following same?

Bob

 

No starting issues, fires right up at any temp. It runs rough sometimes when it's started cold, but clears up after it has warmed up a bit. No recent fuel filter change, but I am at 15k miles since the last change so I am wondering if it is due to the filters possibly being clogged up. It's never not started for me.

 

I change those filters and shine a light in that housing and have a look.

 

Looking at my calculations as to what was in tank Wednesday when I filled it I calculated wrong. I would have had about 9.3 gallons. Calculation is based on fuel purchased, filling to brim (adds 3.5 gals after pump cuts off above normal), and a normal capacity of 38 gallons.

There is a picture of what I am guessing I have for a fuel pickup and the check valve in the link I have below. My plan is to drive it till below 1/4 and see if problem occurs again; if it does then I will drop the tank and have a look.

https://www.ford-trucks.com/forums/1...-stalling.html

I have found posts where owners found this pickup loose and it fell off when removing assembly too. I assume that the purpose of the check (or is it a vacuum relief) is to allow the pump to draw fuel from above the lower pickup if the screen gets plugged.

I guess if I drop the tank I will do the 'hutch' or 'harpoon' mod. I actually did this on my 06 prior to ever filling the tank once I brought it home new.

Bob

 

Hi Bob,

Sorry to hear about the problems you're having! Please let us know what you find out when you drop the tank!

 

To refresh:
1) after pulling RV to lake; tank is just above 1/4 tank; next morning start truck to go get boat from storage, it dies as soon as I put it in drive. It starts back up and I go get boat. Shut it down to get gas in boat; shut it down again back at camp spot; launch boat; later retrieve boat then back to camp spot with truck parked with left front lower than rest of truck.
2) next morning everyone is in the boat and son-in-law starts my truck to go launch boat; truck dies; repeats this several time. We unhitch boat and push truck down hill out of way. Called local dealership and was going to have them come get it but their service was closed on Saturday. Launch boat with SIL's truck. Later in day try starting 'off and on' several times w/ no luck. Decide to check water separator; get nothing but pure diesel; do the KOEO cycle several times to purge any air from me draining separator. Later after reading code want to check injection pressure while cranking and the darn thing started.
3) starts next morning; hitch up fifth wheel; drive a few miles and fill up with ULSD and start trek home.
4) couple of days later; fuel just below 1/4 tank parked on level ground after sitting +8 hours while I was at work..... I start it and it dies; I do the key cycle w/o starting several times and start it up and head for fuel station to fill it. Decide to drive and see if it does this again when the level gets below 1/4 tank.
5) It gets below 1/4 tank; starting fine; keep driving; so I let it set several days, but it keeps starting okay; so now I am below 1/8 tank, I even park it backwards in my inclined drive with the front down and let it set several days but it starts right up

6) Today w/ it indicating 37 miles to empty and somewhere below an 1/8 tank I decide to drop the tank and take a look. My pickup assembly is 15 inches long and it is 15 inches to bottome of tank; I measured 2-1/4 inches of fuel still in tank at that location. This would put the level below the mid point of the pickup by-pass valve (and this isn't perfect measurement of fuel level because this was with tank resting on driveway and it isn't at exact same angle under the truck).

The pickup is not hard plastic; it is somewhat flexible. I removed the screen on the bottom and plugged it (pickup assy) with my finger while blowing on the top and the check valve held fine; which would blow my theory of the diesel leaking down when the truck was below 1/4 tank thus introducing air. I would have just liked to have plugged this check valve but did not have a good plan for doing same as I would want something I know diesel would not soften (like a stainless steel plug) The ID is about 7/8" and OD is about 1". Another member did plug his and here is a link to a thread with detailed pictures.
https://www.ford-trucks.com/forums/8...d-for-3-a.html
My check valve was red/orange as his but frankly I don't see how it could 'fall' out; my design did not look exactly like his internally.

So I did the harpoon mod (which is whacking off the vent pipe insided the tank going to the upper fill pipe assembly). Put it all back together; KOEO cycle about 9 times; started right up; drove 1-1/8 miles to station; 1/2 bottle DieselKleen and filled with ULSD. 36.246 gallons to fill to the brim. Was able to squeeze just over .6 gallons after pump shut off; use to be 3.5 gallons.

I'm not sure what was going on; maybe something got under the little check valve; but how and why as the bottom of the screen was totally clean; and nothing but diesel in tank. In theory my check valve has never had any reason to open and it seems to be working as designed. I plan to not let the level drop below 3/8 tank unless I am on a road trip; and then I will fill it before shutting down for the day if below 3/8 tank.

Question for the Vloney or other Ford techs: when one gets air in low pressure side I assume some air will get in the high pressure side of the HPFP. Is this true? If you get some air on high side will it eventually get out thru the fuel return to the tank, etc? I guess I am asking if I should take it in and have the high pressure side checked for air?

Scares me if I have gotten air to make it to the high pressure side thinking what it is doing to the HPFP. I recall Vloney's comments about the concerns over the air bubbles; and after the many other reads of HPFP failures I am thinking too much

Closing, I don't recall dropping the tank on my 04 or 06 being as much of a chore. I don't know if it is this tank being larger or just me getting older.

Bob

 

Maybe I'm answering my own question; looked at fuel system in 6.4 bible; page 50 of book or page 29 if you have the fuel section only document; the schematic flow diagram of the engine mounted fuel filter shows two air bleed orfices and text pasted below confirms.....

looks like it separates water too! and returns same to tank.

"The engine mounted fuel filter assembly also regulates fuel
pressure by releasing excess pressure via a return fuel line
back to the HFCM. The engine mounted fuel filter also contains

air bleed orifices to remove air and return it to the tank."

Bob

 

I really wonder if this is correct as they do not show the Water Separator for the HFCM; plus the engine filter doesn't have Aquabloc IIRC.

The general description of the engine mounted filter doesn't mention water separation either.

Can't confirm in 'workshop' manual either.

My initial query was in respect to removal of air from the high pressure side and it does look like from the schematic and the descriptive text that same is provided for.

Had to make new post to get the image link in...... as could not from edit options after the fact.

Bob