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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!
 

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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.
 

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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.
 

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Discussion Starter #7
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 ;).
 

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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?
 

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Discussion Starter #9 (Edited)
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.
 
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