Very Excessive Backpressure / Very Low Boost

[jimdawg185]

Little frustrated.
2004 6.0
egr delete, livewire with IDP street tune
unless the sensors are out of whack, Im getting 50ish psi backpressure and no boost at idle and only gets worse from there.

Most boost I can get is 15psi or so with over 100psi of backpressure.

VGT seems to make no difference, you can hear is hissing really bad even after it warms up. Unhooked you can hear the vgt let up and stop hissing but the backpressure doesnt change. I can command the vgt off and on and you can hear it stop hissing.

Ideas?

Most likely started doing this after the dealer put a couple of updates and a rebuilt turbo on it. The hissing was noticable after the egr delete was done. I thinking because the backpressure has no where to go now.

Truck only has 25k on it.

 

[04stroker]

What are you pressures like map, Ebp, and baro koeo?

 

[jimdawg185]

Didn't check with the koeo. Ill check. I do remember the baro being squirly though.

 

[slc dzl]

Is the ebp sensor good or clogged?

 

[DEEZUZ]

Clogged cat

 

[jimdawg185]

Map is 14.32
Back pressure absolute is 14.3
Baro is 14.25

Vgt is 71% at idle

 

[jimdawg185]

Back pressure seems much more reasonable on AE vs the outrageous numbers the sct is giving me. Absolute BP is in the 20's driving with 4-6 psi of boost.
Is it possible this turbo just has a very noisy vgt??? Hissed real loud!