To complete suction of all intake and exhaust valves before starting without applying load to a battery by setting the number of intake and exhaust valves which suck at the same time according to a parameter showing the battery output capability before starting of an engine, and sequentially sucking according to the set number.

A solenoid valve 1 is controlled to drive by a solenoid valve drive control device 30 including a microcomputer 31. In the control for the solenoid valve 1 at starting, before starting, the number of sucking valves 4 is set according to the battery voltage, that is, the output capability of the battery. According to the preset number of the simultaneously sucking valves, the valves 4 are sequentially caused to suck, and after all valves 4 complete suction, engine starting is started. Thus, load applied to the battery can be reduced. Further, when the battery condition is good, all valves 4 are simultaneously caused to suck, so that the valve suction time can be reduced so as to early start the engine.