BMW Repair: white smoke from exhaust, touchless car wash, service engine soon light

Question
Hello!  I have just bought my first bmw - a 2003 325i - 90,000 miles -vin# wbaet37463nj38170- very well maintained - my problem started when I took it to a touchless car wash - not knowing a thing was wrong - I left the car wash and pulled into a convenience store and a HUGE amount of white smoke began pouring out of the exhaust.  No engine lights of any kind came on - the car ran smooth- after running and smoking terribly- (I can not stress this more - it was smoking TERRIBLY) - for about 30 minutes the smoke stopped - while it was idling and smoking I kept a very close eye on all gauges and everything was fine.  From that point on - when I drive the car it will drive so well and out of the blue there will be a slight miss - when you shut the engine off and restart - the smoke from the exhaust returns - but not nearly as badly or for as long as it did the first time.  Usually I can drive a few blocks and it will disappear as quickly as it appeared.  Tonight I noticed a miss when I was at a stop light - when I accelerated it ran great - when I stopped and let it idle for a minute - it started "clattering" and the service engine soon light came on.  I cut the car off - restarted - it smoked for a few minutes - engine light was off -and ran great on the way home.  The smoke is whitish in color and absolutely does not smell of antifreeze - it is more of a burnt smell.  It is extremely embarrassing to drive a drop dead gorgeous bmw with white smoke pouring from the exhaust! At first I thought this might have something to do with something getting wet at the car wash - I am just not sure - it has been doing this for about 2 weeks. Maybe a coincidence?  Please help!!

Answer
What you need to do is check you fluid levels to make sure they are correct.The white smoke normally is a coolant issue so check the radiator.I have never heard of it "just happening" so something bad has happened.Have the codes checked as well it will help with diagnosis.