When cranking is started, a control unit of an ECU determines an advance amount by which an intake valve closing timing is advanced from a fully retarded position toward a bottom dead center, and transmits the determined advance amount to a variable valve timing mechanism. After cranking is started, the control unit determines that there is an abnormality in the variable valve timing mechanism, when the advance amount is larger than 0, and when an actual intake valve closing timing, determined using an intake cam angle from a cam angle sensor and a crank angle from a crank angle sensor, is not advanced from the fully retarded position. When it is determined that there is an abnormality in the variable valve timing mechanism, the control unit outputs a control signal to an inverter to increase an output torque of a motor, which is a driving source for cranking.