There is no PCV valve on an 850 motor, they have a piece called a flame trap. However, there is no flame trap on the turbo from what I understand (my car is N/A), only the oil seperator, check all that plumbing and the seperator, maybe it's clogged up. It sounds like you might have two seperate problems though. You might be getting oil smoke out the exhaust due to a bad internal seal within the turbo, where turbo oil is slipping past the seal within the turbo housing and getting vaporized and thrown out the exhaust, causing the smoke. This would require a turbo rebuild or a new turbo. The second problem might be related to the clogged crankcase breather plumbing as mentioned above, and causing the oil vapor your seeing around the motor.