I can't seem to find where this vacuum line terminates. It starts in the first picture on the passenger side of the manifold. It goes into some sort of valve behind the AC canister and splits (second picture). A thin rigid line looks like it goes into the HVAC box and another vacuum line comes out and is just open and drawing vacuum (third picture).

I can't find any diagrams on this and the only information I find says it's supposed to be capped off at the manifold. I can't find anything within the length of that hose.

Any idea where this goes?

 

I figured it out this morning with fresh eyes. It goes to the vacuum reservoir under the battery tray that looks like the Deathstar.
I knew it had to be something like that but just couldn't see it. I was beginning to think someone stole the part while the van was on the lot. I just bought it.

 

Yep. It's kind of hidden and hard to see unless you take the battery tray out. Glad you figured it out and put the solution on here for someone else to find in the future.

 

Always post your vehicle info please.
It's not a bad idea to replace vacuum hoses while you're in there. They deteriorate fairly quickly and cause all kinds of engine and HVAC issues. Bulk vacuum line is pretty cheap. Same with the checkvalve.

 

Yup, that's what I was doing when I found it was unplugged. I pulled the doghouse for the first time yesterday, just to go through everything, and saw how bad the line looked. The hose from the EVAP solenoid wasn't even there. Just a bit on each nipple. I'll go ahead and order a check valve too.