Engine: What's that pipe?

[B5-4ever]

This is a 3-in-1 post for a Passat B5 199/98 AHL 1.6L engine.

I'm trying to do some engine vacuum troubleshooting to see if that's what's choking my performance and I cannot find an appropriate place to stick the vacuum gauge. But that's another issue. This post is about some piping in the engine that I cannot quite place.

Photo 1 shows where the pipe is. Under that shiny plate, is a pipe that is boted onto the cam cover and it is closed off (and does not seem to go anywhere else into the cam cover).

http://i339.photobucket.com/albums/n461/b5-4ever/My%20B5/Engine/whatsthatpipe1.jpg

However, the other end disappears behind the engine and connects to the air intake after the mass airflow sensor but before the throttle body as shown in photo 2.

http://i339.photobucket.com/albums/n461/b5-4ever/My%20B5/Engine/whatsthatpipe2.jpg

What's this pipe for (shown in yellow)?

Second, when taking these photos, I noticed that wire hanging loosly (red circle) from that harness (red arrow). What could that be, and where should it be connected?

Finally, what's that terminal encircled in green and that is it sitting on?

Thanks in advance.