So I have this whistle sound around the turbo when you rev up. The local mechanic said it was the egr-cooler and it would cost pretty much to fix. So... I did it myself but the whistle is still there. 

I then detached the vacuum hose for the egr - cooler and it became silent. When I put my thumb over the end of the hose, the whistle starts again. Does anyone know what next to do? 

Follow the hose inspecting for damage and/or use a length of tube to your ear like a stethoscope to pinpoint the source of the whistle.