Smoke on start up

[Ratanui]

I was also under the impression that smoke on start up from time to time was normal (it's in the owners manual). As pointed out, it may be worse when parked at a certain angle or left for more than a few days between start ups.
The way I understand it is that there aren't any oil sealing rings on the pistons (in addition to the compression rings). This allows small amounts of oil to seep past the compression rings over a period of time. The old "K" series BMW motorcycle engines had the same "problem". I can't remember exactly, but you would always get more smoke if it was parked on the side stand (as the oil would drain more freely through into the cylinders) than when it was parked on the center stand. Or it could have been the other way round.
The similarity being that the BMW engines in question have a flat inline 3-4 cylinder engine and the Porsche a flat 6 boxer.

[97 Boxster]

I think they key here is that I am having the sucking from the oil tube when I remove the cap. Can you all clarify that this is a sign to replace my AOS?

Regardless of whether or not my car smokes on startup (Which it only did on 2 occasions since I have had the car for 2 years) I should still get my AOS replaced.

Thanks for the heads up.