OK, here is an interesting one...

After long trips, my 2005 A6 3.2 smokes heavily on restart after sitting for more than 3 hours after the trip. I travel for a living, and this is a DRAG!

The scenario is as follows:

Drive for 3 hours or more, park the car, come back after 3 or more hours and start the car back up. It smokes heavily (black/blue) for about 15 seconds and then dissipates (both exhausts). The car has always run fine, no performance or mileage degredation. This does NOT happen if I drive for shorter periods of time (under a few hors, or my 15 minute commute to the office).

Dealer has been responsive, but has not resolved.....

Help!

 

Sounds likeit's running rich. It could possibly be valve seals but since the car's not that old I wouldn't think that would be it. How many miles do you have? If it is rich it could be a bad injector, faulty fuel pump, or computer problem so you might have them check those out.