Volvo: S70 White Vapor/Smoke, blown head gasket, combustion gases

Question
Hi Ray.  Thanks for your help.  I have a 1999 S70 w/ turbo and 101K miles.  Every once in a while as I'm driving or sitting at stop light white exhaust begins...it doesn't have an oil smell but more of a vapor smell.  If I put the car in park and just let it idle the white exhaust begins almost immediately and will not stop until I drive for a couple of minutes.  This trouble just began 5-6 weeks ago and shows no sign of getting better or worse.   The car is still running great, but since this began it does seem that the transmission is not shifting quite as smoothly.  It's been suggested that it could be the catalytic converter, a ring sticking in a cylinder and a bad modulator valve and a blown head gasket.  Any help with what this is or how to proceed would be greatly appreciated.  

Answer
Bob,
Most times the white smoke means blown head gasket. There is a test to see if there are combustion gases in the cooling system. The converters sometimes breaks inside and rattles or clogs the system. I have ever know one to cause smoking.
The trans maybe has a code to be read or check the fluid to see if it is low and or dirty. Make sure the mode switch is in E or S also, not stuck half way between.