under the hood the base engine in the 2015 ford fusion is a 2 5 liter 4 cylinder but we suggest moving up to the se sedan where you have your choice of the 1 5 liter 1 6 liter or 2 0 liter turbocharged 4 cylinder engines all of which can run on regular gasolinehe 2015 ford fusion energi can go up to 21 miles on a charge meaning many people could go for weeks without refueling but with a gasoline engine backing it up room for five and a total range of 620 miles it s also good for road trips