2.0 TDI PD Crankcase questions

Discussion in 'Audi TDI forums' started by Alexander Nikolaisen, Apr 25, 2017.

  1. Alexander Nikolaisen

    Alexander Nikolaisen New Member

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    Car:
    Audi, A4, B7 2.0 TDI & Audi, S4 2.2, 1992
    Location:
    Norway
    Hi, im new to this forum and have some questions regarding crankcase pressures in my BPW engine.

    Please dont talk about replacing the turbo and injectors, no issues there.
    I over time i have positive pressure building up in my engines CCV system.
    I removed the oil filler-cap with engine off and that relieved some amount of pressure.
    I tested the CCV vent by pressurizing the crankcase through the line going to N75 valve and that verified my concern.
    This causes blowby issues to my turbo, wich again generates smoke at idle sometimes.

    Question is: shouldnt the CCV system prevent this from happening in the first place?
    Or should i even bother taking off the cover and look at it? :).

    Thank you very much in advance!
     
    Last edited by a moderator: Apr 25, 2017
  2. chittychittybangbang

    chittychittybangbang Administrator

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    Diesel engines have a lot of blowby. The vacuum pump also exhausts into the valve cover. As long as the pressure is going out back into the intake it's normal.
     
  3. Alexander Nikolaisen

    Alexander Nikolaisen New Member

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    Audi, A4, B7 2.0 TDI & Audi, S4 2.2, 1992
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    But some pressure is building up in the crankcase before the ccv starts to vent. Is that normal? :)

    Tanks for reply :)

    Sent fra min SM-G930F via Tapatalk
     
  4. chittychittybangbang

    chittychittybangbang Administrator

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    If you remove the oil filler cap and feel pulses of air, that is most likely normal. As soon as the engine starts turning over, the vac pump is exhausting and putting out air.
     
  5. Alexander Nikolaisen

    Alexander Nikolaisen New Member

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    Nevermind.. my oilpump failed today anyway.
     
    Last edited: May 3, 2017
  6. chittychittybangbang

    chittychittybangbang Administrator

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    OK, sorry. I'm guessing the engine is bad now.
     
  7. Alexander Nikolaisen

    Alexander Nikolaisen New Member

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    Audi, A4, B7 2.0 TDI & Audi, S4 2.2, 1992
    Location:
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    Update:

    My balance shaft is now changed. my key was rounded in the oilpump not balance shaft. Seems like this design is still an issue.
    The oily smoke was coused by clogged/malfunctioning CCV system. Bought new valve-cover from Audi and exhaust smells like candy now :D.

    i made a crappy video to illustrate the CCV issue ;).
     
  8. Epimetheus

    Epimetheus New Member

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    Audi A4 Cabrio B7 2008 BPW
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    Alexander - I have exactly the same motor as you and I've diagnosed the same problem. I had a quick go at getting the cam-cover off and it seems to be impossible to do so without removing the EGR. I didn't pull it too hard as I just had a few minutes to investigate and didn't want to get myself in a mess with a jammed cam-cover.

    Did you need to remove the EGR (and therefore everything else that bolts on that side of the motor) or did you manage to get the cam-cover off more easily?
     
  9. Alexander Nikolaisen

    Alexander Nikolaisen New Member

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    Audi, A4, B7 2.0 TDI & Audi, S4 2.2, 1992
    Location:
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    Hi Epimetheus.

    testing the breether:
    I did not remove the valve-cover to diagnose the failed CCV.
    I pulled off the vacuum line to the "N75" solenoid (before check valve) and plugged off the crank-case breether hose.
    Lightly pressurized the engine while listening to the breether. Mine built pressure before releasing it through the breether pipe. this was also pressurizing the turbo-drainpipe and pushed oil through the turbo-seals. Under normal driving the tandem/vacuum pump is exhausting into the cylinder head and presurized the engine that way.
    Changed my valve cover and the engine was breething again without any pressure buildup.

    I can make a short "how to" video for you if you want to?

    Removing the cover:
    You do not need to remove the egr to get the cover out.
    unscrew the cover (the screws comes out with the cover, you do not need to pull them out)
    remove the top part of the timing-belt cover and pull the valve-cover up and to your right.
     
    Last edited: Jul 17, 2017
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  10. Keithuk

    Keithuk Super Moderator

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    Its actually Positive Crankcase Ventilation (PCV) not CCV. ;)
     
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  11. Alexander Nikolaisen

    Alexander Nikolaisen New Member

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    Audi, A4, B7 2.0 TDI & Audi, S4 2.2, 1992
    Location:
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    CCV- Crank Case Ventilation
    PCV- Positive Crankcase Ventilation
    "tomayto, tomahto"
     
    Last edited by a moderator: Jul 18, 2017
  12. Epimetheus

    Epimetheus New Member

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    Hi Alexander, Thanks for the information. I worked out how to fit the cover in the end and my car is running fine again now.
     

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