An air-fuel parameter control system includes an injector, an air-fuel parameter sensor, a fuel film parameter calculation module, an air-fuel parameter prediction module and a fuel injection calibration module. The injector injects fuel into an intake manifold. The air-fuel parameter sensor detects a detected air-fuel parameter in an exhaust pipe. The fuel film parameter calculation module calculates a fuel film parameter relating to a fuel film accumulated the intake manifold based on the detected air-fuel parameter, an amount of the injected fuel and an amount of air flowing into the engine. The air-fuel parameter prediction module predicts a predicted air-fuel parameter based on the detected air-fuel parameter and the fuel film parameter. The fuel injection calibration module calibrates the amount of the injected fuel based on a difference between a reference air-fuel parameter and the predicted air-fuel parameter.