[s-cars] Poof! No Boost!

[lebakken1 at netzero.com]

Well, yesterday I have encountered my first S4 anomaly. My boost has disappeared, and the car is running like it is naturally aspirated. Problem manifested yesterday afternoon. I do not have a boost gage (actually, it is resting comfortably along with the rest of many uninstalled Audi bits), so I do not know if boost is completely cut. There is definitely no WHAM anymore, just linear torque.
I guess I will start with the hose at the drain, then continually check other hoses. One was under the manifold correct? This hose would also give this symptom?
It will be interesting. Good thing my wife is going out of town for a couple of days this weekend. I can afford to take it down for awhile.
Any suggestions appreciated.
Regards,
Craig Lebakken
94 S4