I just got my dash back in for the 2nd time this week while working on the evaporator core....and now my air wont blow thru the vents. I dont have my gauges in the jeep just the dash shell. I turned the jeep on and it ran for 15 mins while I searched all over for a vacuum leak and couldnt hear anything. So i went down to the vacuum ball and followed it up from the front bumper. Hoses were fine past the battery and cruise control...but after it makes the 90* turn behind the washer fluid, there is a "T" value and it has an open end. It isnt sucking air at all. What connects to this??

WHere does the initial vacuum line start? Please help!!! Im going on 2 weeks with it torn apart and need to get it back together. Thanks in advance.