ccv valve - root of my various oil leaks?

[Richard7666 0]

I've had quite a few oil leaks (sump gasket, oil level sensor, and now oil being forced out filler cap) in the 18 months I've owned my e46 with n42 engine.

My cousin has suggested it may be a pressure issue forcing oil out, perhaps stemming from the ccv ('oil separator' in BMWs part parlance I believe?)

Would this be a likely culprit? Presently a rather large amount of oil is getting forced out the filler cap! (I've checked it's on correctly)

[charles28 136]

On my E39 530i the CCV and related parts were all cracked and broken, causing oil to leak.

I've had to fix a lot of oil leaks on my car, finally its leak free, it also seemed to run better once i replaced the CCV and related plastic pipes.

[allan 295]

Richard do you have access to a BMW parts catalog ie realoem.com or bmwfans these will help you out. The N42 motor does not have a good rep when it comes to oil leaks and that is putting it mildly. Should the ccv be blocked then this could the reason for some of your oil leak problem google it and it might help you with some method to prove or dis prove that the problem is the ccv or associated hose which might be blocked. To replace this valve and associated hoses requires the removal of a number of items as it is tucked away under the inlet manifold fiddle and a pain in the rear. Sure some one will chim in with a bit more knowledge than I and help you out.

[Richard7666 0]

So my cousin replaced oil separator (after fiddling for 2 hours to get the intake manifold out, two very awkward to get to bolts!) and it was full of crap, completely blocked. It looked like it was full of baby poo!

So hopefully that fixes the constant leaks!

Wish we'd taken a photo.

Edited January 20, 2015 by Richard7666