The 1999 Audi A6 is available as a 4-door, 5-seat sedan. Starting at $36,600, the 1999 Audi A6 AWD Wagon is powered by a 2.8L , 6 -cylinder engine mated to an automatic transmission that returns an EPA estimated 17-mpg in the city and 27-mpg on the highway. The top of the line 1999AudiA6Base , priced at $ 33,750 , is powered by a 2.8L , 6 - cylinder engine mated to an automatic transmission that returns an EPA estimated