Originally Posted by Concillian
The LV at idle indicates a leak, but trims aren't terrible anywhere else. Boost dropping below 10 indicates what is most likely a mechanical issue. It's possible Scott messed up the ROM in some way, but not likely.
It does very much have the symptoms of a post-turbo leak... it's small under vac, which only really affects idle trims dramatically. Under boost it's larger, affecting AFR.
He probably started charging because he realized you want help troubleshooting what he has determined is a mechanical issue.
Was your boost leak test after you had these symptoms? What psi did you pressurize to? and what did you use to attempt to detect the leak?
Hmm - so that could be the TGV or Intake Manifold gaskets, since I already tested out the Intercooler and TB coupler, right? Replaced the Y-pipe gaskets ahead of time. I've had it smoke tested, and pressure tested to 20 PSI.
The pressure test was also after the symptoms occurred, and I used soapy water for that test.