Audi 80TDI, strange noise when over 2k rpm

[warmfuzzies]

Pretty much in the title really, when I go over 2k rpm, and on load I can hear what can best be described as the wastegate venting, though I've no idea if it is, or how to test it. I can though only hear it when the windows or sunroof are open.

All the hoses are ok, theres no obvious leaks, I can see no soot or oil residue, I've stripped and cleaned most bits, and can't find a split hose etc,

It seems a little down on power compared to other VAG models, but I put that down to 238k on the clock...

Any ideas?

TIA

Kevin

[balb0wa]

may be a bad hose, you need to get it on a rolling road, some cracks in pipes are not visible till you get it on the rollers