When the operating characteristics of an intake valve are changed by an intake valve stop mechanism, an ECU outputs a command signal (control on) to a solenoid. At this time, a timing, at which the command signal is output to the solenoid, is determined on the basis of a rotational position of a crankshaft, calculated from a signal of a crank position sensor. However, the output timing is corrected on the basis of a rotational phase difference of a camshaft with respect to the crankshaft.