Engine Help A Dummy Out! Pcv Valve Plumbing Question

Discussion in 'Fox 5.0 Mustang Tech' started by Husky44, Mar 27, 2014.


  1. Husky44

    Husky44 Active Member

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    In a hurry to finish the build of my 67 convertible restomod for the 50th in Charlotte. Running a 5.0 from a 91 LX, with TF intake, heads, no EGR system, no smog anything.

    I have the PCV valve installed in the back of the lower intake. There's two connections on the valve. Where do they connect to? I would guess one of the two feeds into the air intake somewhere, but not sure where. Is this what connects to the fitting on top of the throttle body?

    I know search would probably reveal my answer, but that takes away from wrench time, and somebody on here will know this off the top of their head. Besides, it gives you the opportunity to beat me up for not searching! :)

    Seriously, thanks for the help!
    #1
  2. kpack5982

    kpack5982 Yeah, it was pretty stiff, but eventually a buddy

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    Block one of them off and the other one goes to a vacuum source on the intake manifold
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  3. Grabbin' Asphalt

    Grabbin' Asphalt Mustang Master

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    Either feed them both to the Intake, one in the middle of Intake and the other to the open end(if its open) on the bottom edge ports on the driver(under side part of intake). If they are plugged then do the suggestion above.
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  4. 89oem

    89oem Active Member

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    the throttle body nipple connects to the nipple on the valve cover filler neck
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  5. Husky44

    Husky44 Active Member

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    Dumb question #2: What does this do? I don't have a filler cap or neck yet for my car (running TF valve covers), but why would I want atmospheric pressure air from inside the valve cover feeding into my throttle body? Is this an emissions control function of some sort? Wouldn't it make more sense to plug the nipple on the throttle body, instead of introducing oily air from the valve cover?
    #5
  6. RacEoHolic330

    RacEoHolic330 I like to dress like a pretty girl SN Certified Technician

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    The crankcase needs to breathe. It's a push-pull type of system. It needs a fresh air source after the MAF meter that is not under boost or vacuum. You won't have to worry about it introducing any oil into the throttle body.
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    Grabbin' Asphalt likes this.
  7. Husky44

    Husky44 Active Member

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    Thanks for the quick reply. Was looking to simplify wherever possible; but at the same time I need to get this done in less than 2 weeks, so I don't want to introduce more problems by modifying where not necessary.
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