Whistle from pipe attached to intake manifold. What part is this?
 

Does anyone know what this port is for and why it's whistling on my 2000 Boxster S?

I found in the PET that the port that attaches to the manifold there is part 996 110 151 00. But I can't find what the hose is that it attaches to. The whistle seems to be in the pipe/hose it attaches to, not this adapter/port itself.

http://986forum.com/forums/uploads02...1529988456.jpg

Brake booster vacuum line.
It's leaking. ;)

Are you replacing your engine? Probably the dismanteler just cut the tube. There's a fitting on the other plenum, too. Opposite end. On manual engines it's on one end, on tiptronics it's on the other. The one that 's not used has a block off plate.

Thanks! No, this is not my engine and it hasn't been removed. I just grabbed this picture to show it. I will see about replacing the line or whatever seals there are at its joints. Thanks.