Pointing fingers at AOS..? or not this time

[Topless]

The short answer is no. Oil does not significantly evaporate into the air. It goes on the ground or out through the tailpipe. Do you notice any oily sooting of the tailpipe? What year car and how many miles?

[Gilles]

Originally Posted by Topless

The short answer is no. Oil does not significantly evaporate into the air. It goes on the ground or out through the tailpipe. Do you notice any oily sooting of the tailpipe? What year car and how many miles?

Hello Topless,

I believe that the vacuum generated by the AOS also helps the piston rings to seal properly. Now, if the crankcase has an open passage (a disconnected hose..) then the AOS vacuum gets lost, therefore burning a slight amount of oil through the now non properly sealing rings...

However, this is my theory and for that reason I wanted to share it here, hoping that someone more knowledgeable than myself will share his (hers) comments, thank you.

Regards,
Gilles
'07 CS with 75k