*FIX* Running HVAC controls WITHOUT vacuum canister

  • Ubernathan
    Ubernathan
    Junior Member
    • 11
    #1

    *FIX* Running HVAC controls WITHOUT vacuum canister

    *Mods feel free to move*

    *For N/A models only, you need a vac canister for turbo models due to boost being introduced to the system that runs on vacuum*

    So this is my 2nd post, but given I had difficulty finding a clear solution, I'm hoping/feeling this may help shed some light on the daunting HVAC / Defrost / Heat problem.

    I was blessed with a car that had the vac canister ripped out and no regards to what went where as far as engine bay lines, so I ran a line from the plenum --> 1-way check valve --> T-fitting --> (1 line to top of water cock solenoid, other to inside firewall to T-fitting supplying all under-dash vac sources). Made a short 3min video explaining and showing this as well for those of you who are visual like I am. Hope this helps some out there with the same problem.
    Fixing Stuck Defrost on 300zx WITHOUT Vac Canister - YouTube
    https://www.youtube.com
    This video will describe the common problem of the AC controls being stuck on defrost / venting hot air into the cabin if you DON'T want to replace or run th…
    '85 Z31 Drift Turdbox Especial

    "Live fast, die young, and leave a good-looking corpse."

    • 1 like
  • Dunkine
    Dunkine
    Senior Member
    • 255
    #2
    Nice Vid

    Turbos have a check valve on them already.

    A few have done something similar with the Vac canister to keep it from going to defrost when accelerating hard.

    Have you tested it under load yet?
  • Ubernathan
    Ubernathan
    Junior Member
    • 11
    #3
    Originally posted by Dunkine View Post
    Nice Vid

    Turbos have a check valve on them already.

    A few have done something similar with the Vac canister to keep it from going to defrost when accelerating hard.

    Have you tested it under load yet?
    Thanks, just trying to help someone out there. Under load it functions just as it should, so I was really happy about that. I need to charge my AC but I could feel the different between air when the solenoid would open and close under heat/cold.
    '85 Z31 Drift Turdbox Especial

    "Live fast, die young, and leave a good-looking corpse."

    Comment

    • Dunkine
      #3.1
      Dunkine commented
      10-03-2018, 05:15 PM
      Awesome, I may have to toss one on my 89. I have gone through the vac system a few time and can't seem to find the leak.