Vaccum line question

[Luderacer14]

Yea, i bought this 96 240sx a month ago and just noticed one of my vaccum lines were just hanging there. It's from the passenger side of the rear throttle body. I jacked up my car over the week and noticed there was another unhooked line that ran all the way to the rear of the car. I searced and look in the vaccum diagram and I still can't see where it goes or belongs. I tried to hook it up and my vac dropped to -10. It's usually at -20 with the vac line plugged to the boost gauge. Can anyone tell me what that line is and where it goes. Is -10 vac normal?? Thanks.

[onosqv]

maybe a couple pictures would help?

Also, did you compare these to the factory service manual vacuum diagram?