White smoke

[SSquirrel]

Why does white smoke sometimes come out of my cars exhaust? It doesn't happen all the time

[woodchopper]

Probably just water vapour after start up - should disappear when engine/exhaust is hot.
If it is still there after the car is hot - check your coolant level is going down - if it is, and the leak is not obvious - suspect head gasket.
Blue smoke means engine is burning oil -
Black smoke means fuel mixture is too rich.

[oglecorp]

white smoke means burning oil too. probably a worn piston ring or valve stem seal if it is burning oil.