The Audi A6 is a automobile produced by Audi . Audi 's mid-size car was previously named the Audi 100 ( or Audi 5000 in the United States ) , and was released in three successive generations ( Audi C1 , Audi C2 and Audi C3 ) . In 1994 , the latest generation ( C4 ) of the Audi 100 was facelifted and re-badged as the Audi A6 , to fit in with Audi 's new alphanumeric nomenclature ( as the full-size A8 had just been introduced ) .