CCV System Drain Blocked?

[james20]

I have a 2006 330i with the N52 engine and 180k. Previous owner said oil consumption went up from 1 qt/10k to 1qt/3k miles. His tech suspected that the oil drain from CCV is clogged. Car was well maintained per records. Had began to develop leaks at valve cover and eccentric shaft and oil pan. Would CCV issues result in crankcase pressure creating oil leaks?

However my tech said that CCV issues in the E90 are uncommon. This is a N52 engine. Could he have been thinking of the N53 engine?

Any comments? Thanks!

[dworthy]

Oil leaks tend to be cause by old gaskets, and after 10 or so years, it's due to replace the valve cover gasket. Yes on the N-5x motor's, the CCV is inside the valve cover, and being plastic, after 15 years they tend to warp. So if your's hasn't warp and you had to replace the valve cover gaskets a couple of times and it still leaks, I would have a look at the vacuum pump.

I didn't think that BMW built a N53 motor for the U.S. market BTW.

[james20]

CCV in the valve cover? I wish but running my VIN at realoem shows the CCV under the intake as on the M54 in my 2004 E46. I checked the 2007 N52 and it shows a plastic valve cover with the CCV integrated into it and a line for the drain to crankcase.

This confirms what someone said, that the N52 has 2 different types of CCV systems.

[White94RX]

You have the metal valve cover? Then the CCV is under the intake. Plastic valve cover its integrated into the cover.

[james20]

So, if oil consumption went up for no apparent reason and the CCV is the original with 180k miles, is it a safe bet that the CCV is the culprit? I may want to wait and monitor consumption now that the valve cover and oil pan gaskets have been done.

[dworthy]

Yes, it typically can cause oil consumption to double over night if the valve is bad. 180k is a long time on a diaphram, so it would be well worth it to replace it. Now BMW finds it "acceptable" to have an engine burn 1 liter of oil every 1k miles, but IMO that's just way too much as these motors didn't burn any when new.

[flemm2]

Yes, it typically can cause oil consumption to double over night if the valve is bad. 180k is a long time on a diaphram, so it would be well worth it to replace it. Now BMW finds it "acceptable" to have an engine burn 1 liter of oil every 1k miles, but IMO that's just way too much as these motors didn't burn any when new.

+1

I'd say it's not common to have issues with the CCV's per se, but they do clog eventually as the miles are put on. It's definitely due for replacement at 181k.

I did my valve cover gasket, valve cover, VVT gasket, couple other things recently. Getting the valve cover in/out is kind of tricky.. was for me at least, but as White4RX mentioned above if your valve cover is plastic it's integrated. Integrated in my case - N51.

[dworthy]

Also to add, extended oil changes on older motors isn't a good idea either. The engineers designed the car to be low on maintenance for the first 100k miles, after that you have to step up the game. I myself don't do the extended oil change on my E-46's for the past 6 years once they hit the 75k mark. On the F-45 I am going to start changing the oil every year as it will be getting it's last 2 year oil change this year.