hi the other day i notised a whistling noise when i got to certain revs now when the turbo cutts in black smock bellows from the exhaust and the engine splutters and missfirer can anybody give me any good advice apart from stick a 200tdi in (mine is a td)P.S if enybody can give me a good price for supply and fitting a tdi that mite be something for me to think about becouse this engine has cost me a small fortune and its still going up