I pulled off the intake and egr cooler and took the hpop cover off. I could hear air, through the stethoscope from behind near and around the gear in the back with voltage to the ipr.
There were other faint indications of air, i moved the scope to the stc fitting and it seemed like the sound of air got less then when right next to the gear.

I think it's a good assumption that i need a hpop. The other thing was that while trying to get the cover off, i broke it. sooo now i need a cover. Not good.

as a note i was only doing it for 5-10 seconds MAX at a time with intermissions in between "cycles."