05 6.0 died/won't restart

[eric97svt]

I've got an 05 6.0 f350, yesterday I ran to work for a few minutes, came out and it wouldn't restart, running perfectly fine up to that point. Got a ride home, came back later, it fired right up, drove a couple blocks and it died again. Today I went out and scanned it, no codes, ICP while cranking ramps up to 550 or so, ficm voltage stays between 48-49 volts while cranking. Any ideas?

[dannyboy950]

Check your fuel pressure you should also run the bubble test in the fuel filter houseing.
Read the sticky for the procedure. Min Press.45 psi with a mechanical test gauge and adapter.

[dhanna6powerstroke]

Only does this after it's warm? Starts fine cold?

[eric97svt]

Fuel filter housing fills with diesel in a couple seconds after turning the key, haven't checked pressure yet, but with no restriction it seems to have sufficient flow. Yesterday it restarted after cooling off for an hour or so, but now today it hasn't fired when cold. I had assumed i was going to find low ICP numbers, or a high pressure oil leak, but with the numbers i saw when cranking, i'm guessing that's not it?

[dhanna6powerstroke]

Originally Posted by eric97svt

Fuel filter housing fills with diesel in a couple seconds after turning the key, haven't checked pressure yet, but with no restriction it seems to have sufficient flow. Yesterday it restarted after cooling off for an hour or so, but now today it hasn't fired when cold. I had assumed i was going to find low ICP numbers, or a high pressure oil leak, but with the numbers i saw when cranking, i'm guessing that's not it?

Can you monitor FICM voltage?

[eric97svt]

Yup, FICM voltage was steady at 48-49 while cranking

[dhanna6powerstroke]

Checking fuel pressure is next. Have you unplugged your ICP just to see what happens? I know you said it's over 500 psi but everything is worth checking.

[eric97svt]

I unplugged the icp sensor too, still no start...

[kaya@bernhausen]

so icp tops out at 550psi cranking? that's low. i know the rule of thumb is 500psi requirement, but when cranking, in a correctly operating system, the pressure jumps up closer to 800 or so. briefly, of course. but it doesn't top out at 550. i have seen no start cases where pressure teetered between 5-550psi cranking. still no start. if at no time while cranking, the pressure ever exceeds 550, i'd say you have a low icp issue

[eric97svt]

I haven't cranked it too terribly long while monitoring the icp pressure, it may climb higher than that. I'll go check in a little while and see if it continues to rise. It hits mid to upper 500's pretty quickly, I didn't continue to crank once I saw the 500+ psi that is so frequently talked about...