08 6.4 fuel pressure

[B585Ford]

Truck is bone stock besides h&s w dpf delete. Hpfp would be plausible but it has done the exact same thing with two different hpfp

No on the ported rails only thing done is what was mentioned above. The injectors have not been flowed but it only does it on initial start up.....

With my problem, I did eventually flow test the injectors (Swamps) and they tested fine.

 

[B585Ford]

Yes to the OP. Do you or original poster have ported rails by chance?

No ported rails here either.

To the OP,
I wonder if the PCV is sticking possibly from not getting adequate "lube" to cause you problem to only occur at start up but once the "lube" line gets pressurized it allows the PCV to function propperly?

Does anybody know how fuel can go through the lubrication line within the pump?

 

[blownstang91]

Does it every time you restart it. Fuel temp follow our other 6.4. I want to switch the pcm just for fun but I haven't had time to touch it in 2 weeks

 

[TD-5]

,

Not sure if this is what your looking for, or if it helps, the drawing shows the lubrication fuel in yellow.
There has been some discussion in other threads on supplied fuel pressure to the HPFP. IF the factory set up supplies approx 3-3.5 psi via the regulator in the secondary fuel bowl, Under what conditions would I require a supply to the inlet of the HPFP as high as 20 psi?? .Just trying to get my head around this:hammer:

 

[B585Ford]

,

Not sure if this is what your looking for, or if it helps, the drawing shows the lubrication fuel in yellow.
There has been some discussion in other threads on supplied fuel pressure to the HPFP. IF the factory set up supplies approx 3-3.5 psi via the regulator in the secondary fuel bowl, Under what conditions would I require a supply to the inlet of the HPFP as high as 20 psi?? .Just trying to get my head around this:hammer:

Thanks. That is a better drawing than I was using.

I have no idea why you would need 20....well, when my HPFP was bad, it took 20 PSI to get it to run. Most people have said that by 15 PSI you start getting a surge (on a healthy HPFP).