Mine has done it a few times as well, and only under the exact circumstances described by darice57: start the car and move it a very short distance so it only runs for a minute or less, shut off, start again maybe 30 minutes later - a small puff of smoke. That is the ONLY time it has ever happened; never on initial startup, never after the engine has fully warmed up and then is restarted, etc. Temp has never been an issue, coolant level is fine, oil looks perfectly normal.