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Thread: Negative crankcase pressure

  1. #11
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    Random guess: Bad intake valve stem seal(s). Though that might not cause a strong constant vacuum.
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  2. #12
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    Quote Originally Posted by J Wikoff View Post
    Random guess: Bad intake valve stem seal(s). Though that might not cause a strong constant vacuum.
    That is an interesting concept. This was an issue that happened in a days time. On Thursday it was fine.On Friday the hissing began. Could this happen that rapidly? I would guess that a bleed by test would be a way to check??
    Thanks for your reply. I will see what I can find out.
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  3. #13
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    Default Changing intake and lifter valley gaskets

    Quote Originally Posted by dukeofpg View Post
    That is an interesting concept. This was an issue that happened in a days time. On Thursday it was fine.On Friday the hissing began. Could this happen that rapidly? I would guess that a bleed by test would be a way to check??
    Thanks for your reply. I will see what I can find out.
    I have decided to change all of the gaskets. My mileage is down about 5MPG and it seems a bit flat on power. I have not driven much in the last 2 months so I don't think I did anything bad to it. I pulled off the valve covers to see if a trunion had broken or maybe a bent pushrod, but all looks good.

    Can anyone tell me the torque specs for the lifter valley cover and the intake manifold? THANKS
    Last edited by dukeofpg; 08-06-2018 at 11:14 AM. Reason: spelling
    09 Sport Metallic Red G8 GT, Livernois Tune, AR 1 7/8 LT headers with HPC coating, RotoFab CAI, Brembo Brakes, Front Grill Cutaway, GXP Diffuser, Oil catch can (DuclosBrosRacing design) Custom logo Embriodery on headrests Sirius Radio Module




    !!!!!AND A BRAND SPANKING NEW ENGINE AT 35K!!!!!

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  5. #15
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    Default Fixed!!

    Okay, I changed the intake and lifter valley gasket and all is well!! I never saw any issues with the old gaskets, but the problem is resolved.

    I give a ton of thanks to everyone that offered a suggestion of help.
    09 Sport Metallic Red G8 GT, Livernois Tune, AR 1 7/8 LT headers with HPC coating, RotoFab CAI, Brembo Brakes, Front Grill Cutaway, GXP Diffuser, Oil catch can (DuclosBrosRacing design) Custom logo Embriodery on headrests Sirius Radio Module




    !!!!!AND A BRAND SPANKING NEW ENGINE AT 35K!!!!!

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