My wife allowed our 740 to idle in the driveway until she was ready to go to work (idled about 5 min or so), when she arrived at work after about a 10 min drive a chemically smelling white smoke came from unter the front of the car driver side. SHe reported that it didn't overheat and no oil loss. She completed a few trips the rest of the day and I drove it hard for 20 min last night and there were no issues. The only thing out of sorts was that the coolant resv. was abit low; however, it didn't take much coolant to get it back ut to MAX. The car sat for about 4 days without running, could collant have dripped and collected somewhere to burn off or maybe there was a plactic bag or someting buring?

thanks

Michael