I'm sure the AOS has been beaten to death here as much as the IMS but I'd like an explanation why this happens only once in a while not always. If the AOS is bad wouldnt the car alway smoke ? I've noticed only on real hot days when I have been hitting the gas hard and my oil temps are up that the car will smoke at startup after a brief sit. On days I take it easy(when the wife is with me) it never ever smokes. Is it my AOS or could the oil be thinning and getting by the valve seals or rings? Or, is this normal for an aging AOS? My 996 has 82K and soon will be heading to Jake at Raby for the solution and AOS plus other items so I am not worried but would like an explanantion if someone has one. Thanks and love this Forum!