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Excessive crankcase pressure

Discussion in 'Gen 3 Prius Technical Discussion' started by donzoh1, Apr 27, 2024.

  1. donzoh1

    donzoh1 Active Member

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    Five
    My 2013 has excessive crankcase pressure. It runs fine with and has no trouble codes. As Taylor Swift might say, "the ICE has been through it" and eventually will probably be replaced with a JDM motor. Meanwhile, is there a way to tell whether the excess pressure is from piston ring/cylinder wall bypass? I was thinking maybe a half an ounce of oil in each cylinder could eliminate the symptom for a few seconds. Is it a good idea to vent excess pressure? I did install an oil catch can which I empty at each oil change. The engine doesn't burn much oil.
     
    #1 donzoh1, Apr 27, 2024
  2. Danno5060

    Danno5060 Active Member

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    The PCV system should have a slight vacuum in the crankcase. If it has pressure, but it's not the rings, change the PCV valve, and check out the vent lines.
     
    #2 Danno5060, Apr 27, 2024
    PriusCamper likes this.
  3. PriusCamper

    PriusCamper Senior Member

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    I'm always telling people that replacing a PCV valve is a waste of time and concerns about its failing is a throw back to a 1/2 century ago when engines ran way dirtier.

    However... With your symptoms, replacing the PCV would be the first thing I'd consider.
     
    #3 PriusCamper, Apr 27, 2024
  4. donzoh1

    donzoh1 Active Member

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    2004 Prius
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    Five
    My deepest apologies to anyone who was inconvenienced or traumatized by any thread duplication. I don't recall bringing this issue up before.

    Anyway, PriusCamper, thanks for your response. When I did the head gasket (after the dreaded EGR Cooler thing) I noticed some cylinder wear which I was blaming for the excess pressure. I did clean the cooler and the EGR Valve and verified the ball did rattle in the valve but maybe should have just replaced it.
     
    #4 donzoh1, Apr 27, 2024
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