And of course I thought about all the puffs of smoke and the image of new popes lined up out the door of the Vatican and down the street.
Most of us find it difficult to tell the difference between white and light blue smoke out the exhaust, so I wouldn't rule out either one at the moment. A good test would be to pull the PCV valve out of the valley pan and just leave it out of the hole and go for a test drive. If the smoke goes away, then the valve is bad (and the smoke was actually blue). Don't disconnect the PCV valve from the vacuum, just let it sit next to the grommet.