Ac/heater Vacuum Lines

Discussion in 'Fox 5.0 Mustang Tech' started by 6ScubA9, Oct 9, 2013.

  1. Hello all! Brief intro: I bought a 92 Mustgang GT (pics soon) about a month ago. Good price has some upgrades but definitely a project car. The a/c has all the lines ripped out (for more hp i assume). The air only blows out of the defroster vent and from the floor (not really sure if it's from floor vents or otherwise). The defroster blows warm air but not out of the floor. I've read that it's the vacuum lines but there are a lot of them and if it's like everything else on the car it's missing some. As far as anything i've found goes on vacuum lines is to the vacuum tree, no help after that. So if someone could give me a quick rundown that would be awesome! Here's some pics with the questions i have. Thanks!

    This one is on the passenger side and the hose running from the top middle of the picture comes off the split where the a/c line comes from the vacuum tree. How many hoses should come in, what are they, where do they come from? As you can see one hose is routed on two nipples, closing them off i guess? is there something that should go to this?

    and here is the bottom (best angle i could get)

    here are the hoses under passenger dash. how many hoses should go in/out, where do they come from/go?
  2. Diagrams courtesy of Tmoss & Stang&2birds

    Under the Dash HVAC diagram

    Under the hood vacuum diagram


    See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring Everyone should bookmark this site.

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  3. T
    Thanks! That's a lot of info to go through and definitely appreciate it!! I was hoping for "looks like you're missing (applicable hose)" or something to the effect. The diagrams are confusing and was hoping for color real life pics.
  4. Ah man. The pics didn't post. I'll try again to get them up.