A system for controlling operation of an internal combustion engine includes a controller configured to send signals for controlling at least one of air-fuel ratio, spark-ignition timing, and fuel injection timing to an internal combustion engine. The system further includes a sensor configured to send a signal indicative of exhaust gas temperature to the controller. The system is configured to control at least one of the air-fuel ratio, spark-ignition timing, and fuel injection timing based on a signal indicative of at least one of an operating condition of the internal combustion engine and load on the internal combustion engine, and a difference between a target exhaust gas temperature and the signal indicative of the exhaust gas temperature.