Hello,

I am losing oil from my 1999 Passat turbo and have to top up regularly. The car has just under 160,000 miles.

I cannot see any blue smoke or smell burning oil and there are no puddles. When I start the vehicle there is slight knocking until the oil gets distributed. The car pulls well, no lack of power and good economy . Googled the problem and the result was suggesting a suspect PCV valve stuck open,. Youtube video advised to remove the oil cap when the engine is running. I tested this and the cap moves on top of the engine which I believe this means the crankcase is breathing properly.

Any ideas?

Thanks

Mike.