If you live in colder climates like me this is common on these junk E53's. Happens on both 6 and all V8. The kits are a joke and only work the first year. The white milky stuff freezes in your oil if you don't drive more than a half hour each day to work to burn it off, it gets stuck in the PCV valve and oil tubes. This happens around 18 degrees and lower. BMW well knows of the design flaw and ignores it.

The pressure in the engine sucks the engine oil in the cylinders and makes the engine smoke and or causes hydraulic lock and ruins the engine by bending the pistons rods or blows a head gaskets or both.

On my 4.4 it forced the oil out the valve cover fill cap and it never smoked. It did blow my valve covers and rear main seal $2K

The only way I found to help avoid this is 1. don't own a X5 2. Don't start the car under 18 degrees 3. definitely use Marvels Mystery Oil in your oil.

This only happens if you don't drive far each day and the temps get below 18 degrees....6cyl-8cyl, new CCV parts ,it doesn't matter, will happen.

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2002 X5 4.4i Sport Wheels
2014 X5 35i M Appearance & suspension package
1995 Porsche 993
1972 Porsche 914-6
2020 GLE 450 Twin Turbo
2019 Alfa Stelvio 500hp Quadrifogilo
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