The 2004 Subaru Impreza Outback Sport is available as a 4-door, 5-seat wagon. Starting at $19,220, the 2004 Subaru Impreza Outback Sport (M5) is powered by a 2.5L , 4 -cylinder engine mated to a manual transmission that returns an EPA estimated 21-mpg in the city and 27-mpg on the highway. The top of the line 2004SubaruImpreza Outback Sport(A4) , priced at $ 20,020 , is powered by a 2.5L , 4 - cylinder engine mated to an automatic transmission that returns an EPA estimated 21-mpg in the city and 27-mpg on the highway.