I replaced my AOS last fall and I've been keeping a mental log on when I see blue smoke at startup. I've noticed that if I drive the car and park it for a long or short period of time - I have no issues. If I start the car up, pull it out of the garage, wash it, put it back in the garage and drive it the following day I get blue smoke on startup, everytime.
So this makes me wonder if it has something to do with pressure build up in the engine when you start it but don't drive it...
Just curious on others thoughts on this hypothesis.
-Steve