Can someone tell me what the technical name is for this part and exactly what it does. Mines not working so need a replacement. It does something with the turbo....can't remember what my mechanic called it but he said they were hard to get hold, or at least VW don't do them any more? I'll post a wanted once identified.

Cheers
Dan
ps I've just realised what the red line could be interpreted as, it's the part of the engine that I need identifying


