What is this white smoke without warning?

[huston]

white smoke emits when i start the car. there is no warning sign. the temperature is stable and no check engine warning too.

What then.

[Nehmaiz]

What year model is ur 911?

if the white smoke only stays doe 3-4 seconds when u start the car, the usual culprit is the AOS (air oil seperator). Nothing major, comon problem, easy fix...

However if ur afraid of a blown head gasket i would check the oil for any traces of coolant, and possibly the sweet smell of coolant in exhaust smoke. Has the car overheated lately?