Cruising down the highway, the efficient[1] gasoline engine kicks in the horsepower without hogging the fuel.
[1] 40 city/45 hwy/42 combined mpg. Based on 2010 EPA mileage estimates, reflecting new EPA fuel economy methods beginning with 2008 models. Use for comparison purposes only. Do not compare to models before 2008. Your actual mileage will vary depending on how you drive and maintain your vehicle.