Your wastegate is bad! The wastegate has a small hole in the housing used to relieve pressure on the back side of the wastegate diaphram. The heat from the turbo kills this diaphram and the whistle you hear is from this hole. Replace the wastegate accuator and the problem should be fixed! My car...
If you have a air/fuel meter watch it. does the meter switch lean to rich or does it hang in the lean for awhile? My car does the same thing and mine apears to have a lazy upstream 02 sensor.
All my lines appear to be ok. I searched for vacume leaks and found none. i was watching the o2 volts on my snapon modius and my long term fuel trim was at 25%. It would drop to 9% off idle. I also pulled the vacume line off the fuel pressure reg and sprayed T-Body cleaner into it. My o2 didn't...