I think it’s part of the vacuum system. 1996 VW Jetta VR6 12v. Pics below the jump. The car somehow still magically runs without this part attached; the guys at autozone just stare at me blankly when I point to the part. I don’t trust the dealership with it since they’ve broken more parts than they’ve fixed. Looks like the rubber boot connecting this to the engine deteriorated over the last decade. Now my car runs like it has a lumpy cam. The problem is that nobody knows what this part is, so I can’t order one. It should be just a couple of pipe clamps to loosen/tighten to replace the part…. once I can order it.