The 2012 Toyota Sienna is available as a 4-door, 7-seat passenger van. Starting at $25,060, the 2012 Toyota Sienna Base 7 FWD is powered by a 2.7L , 4 -cylinder engine mated to an automatic transmission that returns an EPA estimated 19-mpg in the city and 24-mpg on the highway. The top of the line 2012ToyotaSiennaLimited AWD , priced at $ 40,570 , is powered by a 3.5L , 6 - cylinder engine mated to an automatic transmission that returns an EPA estimated 17-mpg in the city and 23-mpg on the highway.