I have notice 3 times now that my 12 CMS will put out this big puff of white smoke at start up. 2 times it has happened in the morning after sitting all night and then last night it was when I came out from dinner and it had been sitting for about 2 hours. It only smokes for a few seconds but it is a pretty large amount when it happens. Has anyone else noticed this and is it something to be concerned with?

 

I always get visible white smoke when starting and have since the car was new. It's just water vapor, it goes away when the exhaust warms a bit.

Dave

 

my cms all4 did this occasionally with the stock exhaust system ...

since i installed a milltek dp back system it has not done so ... no second cat or resonator

my guess is the second cat and resonator catch water which vaporizers on the next start