Charcoal Canister Plumbing

[porschedude996]

I’m working on getting my newly acquired 1983 911SC for a smog emissions test and inspection. Hoses a brittle and broken. Most of it I have sorter out, but I can’t find where the third nipple connects. One to the fuel tank, one to the left side of the air box. Where does the single rear facing nipple connect? Or does it remain open to atmosphere?

[Solamar]

Open to atmosphere.

[porschedude996]

Thanks!