Please could you help me i have an a4 1.9tdi 02 plate S-line,just recently i have noticed that when i take my foot off the throttle i get a loud delayed air blowing noise coming out of my air box.If i rev it from standing up to 3500 it does it and then nearly stalls as though its gasping for air.I have taken it to a specialist who plugged it in and took it out for a drive.He said that the turbo is boosting fine and the air flow is ok.This air noise is really loud now i have had the pipes checked by a garage who said none were broken or have popped off,so no one seems to be able to help,this noise is also happening when im driving normally even more so if i grandad drive it and labour the engine,i know my car doesnt have a dumpvalve etc so could anyone help as my car now sounds rubbis and its doing my head in.