03 6.0 with 90k miles. New heads, all orings , stand pipes, injectors , glow plugs, egr delete , oil cooler and studs . Has sct livewire. Just took the truck to the shop for a hard start issue and misfiring at around 30% throttle driving. It would fire up great in the mornings with some white/blue smoke till warm. But after it was warmed up you shut it off it would fire right back up but very slow to reach proper idle .But if it set for about an hour it would crank great start but same lazy idle up but now it wouldn't get over 300 rpm before it would die. And do this for 5 or so more times before finally idling up. Then runs pretty good other than the misfire. So he said it's either the hpop ipr or icp. I had him replace all 3 with motorcraft parts. Still the same issue ! Return the truck to stock tune and it doesn't have any power . My pockets are only so deep ��. Any feedback ????

 

Moved to the 6.0L forum.

 

What pressure is the HPOP producing? It was a Ford Reman replacement?

There are serious issues with those units, known to be bad, the replacements are known to be bad and some guys have been through as many as three or four to find a good one.

Most likely, your HPOP is a bad out of the box unit.

What is the FICM main power output reading, needs to be 45v plus?
Any codes?
What was the ICPV?

 

$5 down on injectors.

Where did they come from, and do you have access to someone with an IDS so the injectors can be tested, compensated and not compensated?

 

But that does not answer why he can't make more than 300 rpm.

Alan, you replaced parts that didn't need to be. Let's get some numbers before doing that again.

Sorry you had to find this site under these conditions, but welcome just the same.

 

Stand pipe o-ring got munched , need to rule out and get some pressure readings ICP & IPR , pull the IPR and see if the screen is intact or full of debris. You are running OEM filter and cap yea?