boost leak test problems

[audi-medic]

for the past several days i noticed my boost/vacuum gauge needle moving slower, almost like i had a leak somewhere, so i figured i would try a boost leak test, i set everything up, connected the compressor and put a max of 12psi to begin with, i also remove the "puck" from my tip and capped that off, with the compressor set at 12 my boost gauge barely moved, i than increased to 20psi and saw that i got 6psi on my boost gauge (in the car), and finally i tried bypassing the turbo into the tubing post the turbo and tried at 25psi and only got 11psi in the engine, my oil is bubbling (which is normal) and i can hear a whoosh sound from the crank but nothing else,

i deleted my SAI, N249, suction jet pump and my vacuum reservoir, i changed all of my clamps, everything seems tight, i went through the entire engine with soapy water and fixed several small leaks in the evap system but nothing big,

at the end of the day it still was not holding pressure....

am i doing something wrong? could it be my boost gauge (vdo)? suggestions?

[ElSabio182]

The actual turbo is still behaving normally, I assume? Could definitely be a busted gauge, my old gauge (also a VDO mechanical) crapped out on me at one point. I did the same thing...hunted down leaks, but eventually gave up and took it to a mechanic, convinced it was a wastegate issue or something. Nope...the gauge itself had shit the bed.

Or you could try a smoke test, I guess?

[Radskull1]

could be a waste gate going bad