I have a 130 1.9Tdi A3. Had it less than a year and from the whole time I can remember there is wooshing/hissing noise that can be heard in the cabin (passenger side) when accelerating. The car seems to pull well but the noise annoys me a lot as I have been in my friends mk4 1.9tdi golf and his is very quiet in comparison. This has led me to believe that I have a boost leak. I have done a little research and it seems that oil stains can often be a sign. My car drips a little bit of oil... And also, on the very odd occasion when accelerating the engine goes into limp mode. Is it worth getting underneath and having a look around? What do I look for? Any help would be great!