About the only thing I can think of now would be a bad HPFP. I don't think a pressurized system can ingest air, so if there was a leak somewhere on the HPFP, maybe at one of the valves, it would suck air and pressurize it in the high side of the fuel system.

As to how I would prove it? No clue!

 

how about making an appointment with your ford service center. the day before your app. take the truck and a set of car ramps there and park it overnight with the pass. side parked on the ramps so they will have to get it started in a simaler situation as your self. just an idea if your truck is still under warrenty.

 

UH, I am a ford tech. This one is currently sitting in my bay for repairs. I have verified the complaint. Just giving you the scenario so you can see what we're faced with daily. #2 injector showed a difference in fuel trim (you can see what the pcm does to control each individual injector). Changed #2, no help. You can control volume control and pressure control valves to see if they're sticking, no help. Come on folks, customer wants his 55 thousand dollar truck back! Fuel pressure low side and high side (running) checks fine. Drive it 100 miles, ok. Park it in the bay with one side raised on the rack, after 10 minutes, wont start (air in the fuel). Hurry, SM is on our back, customer talking about lemon law!

 

subscribing.

 

This is crazy, I'v got to see what it ends up being.
Subscribing.

The old IDI's do this, but it never matter which way the truck is parked.

 

Could it be possible that the fuel supply line that goes between the fuel filter housing up along the passenger side valve cover to the pump could be back flowing past the check valve underneath the fuel filter and back into the fuel filter housing putting air into that supply line? The 6.4 HPFP cannot pump air like in the older HEUI designs where air can work itself out.

 

but where is the air coming from? to me THAT is the question..

how is the air getting into the system..

Sam

 

Isnt there always a air bubble in the fuel filter bowl? When you remove the fuel filter the fuel is never all the way to the top.

 

Line replaced, no change (pita by the way).

 

subscribing also!

 

C'mon folks! Warranty time is almost up! Vehicles are stacking up waiting to be worked on. Wheres all them folks that say dealer techs are incompetent? I've done every test in the book (and some that aren't). Checked for restriction at the low pressure pump, checked to see if the fuel immediately out of the pump was aerated (test not in the book), bled low side and high side at the cooler, checked for biased frp sensor, changed #2 injector, changed all washers and o-rings on injectors, changed all lines to each injector and torqued all to specs. Independent garage techs, speak up. You're only too glad to do it any other time!

 

Maybe customer should try some non carbonated fuel

 

Just a long shot, but the fuel safety switch. Where does it get is information from and where in the system does it shut off the fuel. Could there be an issue at that point?

 

does the cooler have a schraeder value on it? is it possible that due to the reduction in temps (sitting) there is a small vacuum created and the schraeder valve is sucked enough to allow air ingestion.. and with the drives side down (how steep an angle is required?, 1 2x4 on the passenger side, or 10inches for example?).. the air is enough to bubble uphill from the cooler..

I thought it had a schraeder valve I used when I changed my fuel filter and it wouldn't start...

Sam

 

So there was no issue found with the fuel pressure regulator inside the standpipe? The pump has a volume and pressure control valve. Could one of those be the culprit?