HPOP?
 

Ok 2004 Early build. 2290 code give it skinny peddle ICP stays low around 700 to 800 and IPR goes up to 80%+. Let off and ICP shoots up over 1000 and IPR drops to 30%. Truck isn't making boost either only making at 15. My HPOP I know bleeds down when sitting over night I'm guessing it is time to replace?

Sounds like it to me, but hopefully others will jump in.

Have you had any no starts yet , hot or cold ?

Only when nose up on a hill and the truck has been sitting a while. Cheezit has said in previous thread pump bleeds down from seal going bad.

Well she died on me. Can only make about 380 on ICP and IPR is 83%.

Yes he has, maybe pump problem .

Ok just quick update. Been on vacation so I haven't had a chance to see what would happen on cold start. Was parked nose down as always but took aroung 6 seconds of cracking to build any pressure. When it did fire up pressure was reading in the 800 and IPR was in the mid to upper 30s. Absolutely no power. Guess ill get to have some fun in my driveway pulling HPOP.

Should the pump leak back towards the suction side any? Took some shop air to my HPOP on the discharge side and can hear it leaking to the suction side.

if leak is isolated to back of engine, it may be leak from HPOP. replace current stc fitting with updated stc fitting. from ur symptoms, sounds like it's pointing towards the HPOP.

Yeah I have early 04 no stc fitting. Really wish I had a top side creeper.

thats right. my bad. i forgot to see the year of ur model. i dont suppose the early build 04 have the STC fitting, right? or does it? correct me if i'm wrong, guys. i'm sorry. i was in my own little world.

it could be something really simple n straightforward like a worn-out o-ring seal.

I think I should have explained something a little better. I took the pump out and put air to it on outlet side and could hear it coming from inlet side.