What's this hose go to??
 

I just noticed on my 86 951 that is currently a non starter that running along the firewall is about a 1/2" black hose that toward the driver side is a small T off. The tee looks like it accepts a 1/8" or so hose. I have looked but can't see anything laying arround. I am thinking that either knocked it off while swearing atmy reference sensors or that itwasoff since before i bought it. Anyone know what i am talking about and where i should be looking?

RE: What's this hose go to??
 

There should be a small vacuum line connecting there.

RE: What's this hose go to??
 

I have a small vacuum line that runs along the firewall from pass to drivers. But it was cut by the looks of it...it is a harder plastic type line. What does that vacuum line go to? I am wondering when i was busy trying to replace the reference sensors if i knocked it off and tossed it out of the way accidently. Thanks!