Hi, Do you get a slight whistle when boost comes in on your 2.0tdi 170 engine? I've noticed it ever since i bought the car and thought it was just normal (i do have a K&N panel filter fitted). Now im starting to wonder whether it should be doing it or not. Its only really noticeable with the window open. The whoosh starts from around 1300-1500rpm, but what i have noticed recently is that, say, you let off at 2000rpm in gear, the whoosh settles down a little for a second but then comes back again a little higher until the revs drop. Is this normal or not? There is a bit of greyish smoke looking in the rear mirror when you put your foot down to overtake, more so the first time and it seems to die down after the first couple of blasts. It has a DPF fitted too so i didn't think there shoulw be anything?! MOT tomorrow morning so im a little worried, how much smoke is too much?