ive got a mk4 golf 1.9 tdi SE which has a pretty bad whistling coming from the turbo, it was driving and sounding fine, then literally with in a hour i got in it and went to drive it and as soon as i touched the throttle the turbo was making a really loud whistle noise, quite a high pitched noise, sound silly but it sounds almost like a siren in a way. the sound is worse when you drive it and go through the gears, as appose to it standing and reving it. the car isnt loosing any power it still drives the same, it was taken into a garage yesterday and i was told it needed a new seal on one of the hoses, but on getting the car back its no different and the noise is just as bad, and the garage said they cant see were its coming from or what it is. anybody got any idea? is the turbo on the way? or could it be something like a barring or something sinple?