4dr Sedan,4-cyl 138 hp hp engine, MPG: 23 City30 Highway. The standard features of the Kia Optima LX include 2.4L I-4 138HP engine, 5-speed manual transmission with overdrive, side seat mounted airbags, driver and passenger side airbag head extension, airbag occupancy sensor, air conditioning, 15 steel wheels, cruise control, power mirrors, power windows, and power locks.