Noob: Whats this disconnected sensor for?

[Phase16V]

Can anyone tell me what this is for?

Im looking to buy this Phase 1 and the bodywork is in god condition.
The motor i do have som misgivings about, especially this disconnected hose/sensor part.

 

[Mr Underhill]

That pipe goes to the carbon canister.

A bit more info - https://cliosport.net/threads/carbon-canister.783805/#post-11147758

 

[Phase16V]

Thanks!