losing boost at 12psi

[Korben007]

So I am driving home today from my long road trip. I drop it into third and all of a sudden the car hits 12psi(has GIAC usually boost around 15psi) and sudders really bad and drop to 5psi. a little while later it would allow me to boost back to 12psi. studders again and goes back down to to 5-4 psi. this is a very consistent problem. The car idles and drives perfect until i hit 12psi. perfect vacuum on the idle.
VAG COM DTCs
VAG-COM Version: Release 409.1-US


Chassis Type: 8D - Audi A4 B5
Scan: 01,02,03,08,15,17,25,35,45,55,56

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Address 01: Engine
Controller: 8D0 907 551 A
Component: 2.7l V6/5VT G 0003
Coding: 06611
Shop #: WSC 06325
8 Faults Found:
o2 Sensor 17530 - Oxygen (Lambda) Sensor Heating: B2 S2: Open Circuit
P1122 - 35-00 - -
o2 sensor 17548 - Shareware Version. To Decode all DTCs
P1140 - 35-00 - Please Register/Activate
O2 sensor 16544 - Shareware Version. To Decode all DTCs
P0160 - 35-00 - Please Register/Activate
02 sensor 17539 - Oxygen (Lambda) Sensor: B2 S1: Internal Resistance too High
P1131 - 35-10 - - - Intermittent
O2 Sensor 17521 - Shareware Version. To Decode all DTCs
P1113 - 35-10 - Please Register/Activate - Intermittent
Cruise Control 17977 - Shareware Version. To Decode all DTCs
P1569 - 35-10 - Please Register/Activate - Intermittent
16684 - Random/Multiple Cylinder Misfire Detected
P0300 - 35-10 - - - Intermittent
16687 - Shareware Version. To Decode all DTCs
P0303 - 35-10 - Please Register/Activate - Intermittent
Readiness: 0010 0001

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Ive labeled the most of them what they r relevent to. and who had ever had a cruise control failure? thats a bummer.

My only guess is the MAF is not handling the volume of air at 12psi?

any input please?

[RedRocketS4]

boost leak? do a leak test.

[Korben007]

ruled out a boost leak. cleared the codes and the came up again as same misfire on cylinder 3 gonna check that one out. which one is cylinder 3?

[O 16581 72452 5]

ruled out a boost leak. cleared the codes and the came up again as same misfire on cylinder 3 gonna check that one out. which one is cylinder 3?

Flywheel side is 4 your pullies are 1.

[mholme]

ruled out a boost leak. cleared the codes and the came up again as same misfire on cylinder 3 gonna check that one out. which one is cylinder 3?

How did you rule out a boost leak? Did you pressure test it?


From front of engine:
4 1
5 2
6 3
Rear of engine

[BurnAll4S4]

o2 sensor time

[O 16581 72452 5]

How did you rule out a boost leak? Did you pressure test it?


From front of engine:
4 1
5 2
6 3
Rear of engine

D'oh, not a 1.8.