The all-new 2018 Rio is powered by a carryover but enhanced Gamma 1.6-liter GDI four-cylinder engine, targeting improved fuel efficiency, better responsiveness and low-speed driving dynamics. The main features of this unit are a high-pressure fuel system with direct injection, variable intake system, low-friction oil seals, and piston cooling-jets. The well-engineered powerplant also utilizes an aluminum valve cover and block for reduced weight, while incorporating cast iron linings for increased durability.