Romping and hard start

[ProblemChild]

I just bought a 2000 7.3, automatic, 4x4. I was told it has 200cc single shot injectors, aftermarket HPOP, 38r turbo, intake, exhaust, regulated fuel return, and DP tuner.
I have AE if anyone can tell me what to look for.

Heres my problem, the truck sometimes is a little hard to start and blows white smoke. It then idles okay and drive okay for a few min before it gets a rough idle. it runs good under throttle but as soon as i lift off the pedal it gets a choppy idle. The parts are low miles and all bought new. It does not always do this and will get worse if i get on the gas hard then let get off of it. I can make it stop for a few seconds if i have the tuner set higher than stock and turn it down while i give it a little gas. When i do this it get a really quiet idle then starts romping again.
Also sometimes its worse in park than in drive but not always.

I checked ICP pressure and duty cycle at idle and get between 460-500psi at 7-9% duty cycle. If i hammer on it under load it goes up to 3200+psi and 35-40% duty cycle.
I did a buzz test and i can hear them all pretty good(idk how loud the standard is)
I did a few cylinder contribution tests. First one came back good, after running around and doing other tests i did it again and it came back twice with cylinder 3 and 4 balance or something( i forgot how it was worded)

Ideas or things to test for would be great!

[ProblemChild]

Anybody have any ideas?

[Myers129]

do you know what tune you are running in?

[ProblemChild]

I have a TS chip with 6 tunes it does it in every tune, ive tried beans and php tunes. It was so bad i took the tuner off my truck and it actually runs better. Still romps at idle though. I also replaced the pcm with no change.

Im thinking it has to be mechanical. Like i said i have the AE scanner but not sure what to look for.

[Myers129]

This is just a wild guess because all of you're info from ae is similar to mine and my truck is running fine. Has the CPS ever been changed? I know the truck won't run if it goes out but I am unsure if there is an in between for a CPS failure. When was your last oil change and what type of oil are you running? Running some rev x might be an option??

[Turbostang500]

Might want to verify the actual hpo pressure with a mechanical gauge.
Just because the ae is seeing correct pressure, doeant mean that it is the actual pressure.

[ProblemChild]

CPS was changed about 15k ago.
How do i check HPOP with a mechanical gauge?

It only does it at idle. if i bring up rpm just a little bit it stops. Could it ba a bad oil pupmp not feeding my HPOP at idle? Also when i cold start it i can drive around the neighborhood slow andc its fine for about 5min but if i get on main road and get on the throttle a little harder it starts right away.

I dont remember what kind of oil is in it. I had it done at the shop when they put all these parts on.

I also have new ipr. The truck didnt do this before new parts were put on, but sat for 6mo before getting the work done.

[Turbostang500]

What you have going on sounds similar to what you would get with the 10k mod on the icp.

Could the harness or sensor be messed up a little? Is there any oil in the sensor?

You would have to plumb a mechanical gauge in a hpop line. Im not sure on the procedure though.
what about unhooking the icp and driving it around a little to see if it is better.

[ProblemChild]

I just replaced the icp after it started acting up. I got to go to the store in a min anyways so ill try.

Could it be air in the fuel?
ow do i check oil pressure on on the motor (not HPOP)

[Turbostang500]

Im not sure where the factory sensor is.
You can take the cover off of the hpop reservoir and see if it is about 1" from the top.