Plastic valve/sensor on air cleaner

[Hairyone]

Gday,
Can anyone tell me what's the plastic valve/sensor on the top of the air cleaner with the rubber tubes attached on a 1996 22R is?
What's it called?
What does it do?
How does it work so I can test it?

Ill try and attach a photo.

Thanks in advance....cheers

Hairy

[Hairyone]

Ahhh.....
Could it be a thermos switch that activates a vacuum causing a gate in the intake to open/close drawing air from around the exhaust for cold starts?????
I can just disconnect it if that's the case?