CONTROL DEVICE FOR ENGINE

A control device for an engine includes a valve-stopping mechanism which holds intake and exhaust valves of the first and the fourth cylinders (idle cylinders) of four cylinders in closed states, a throttle valve control unit , an ignition period control unit , and an ECU which controls the valve-stopping mechanism , the throttle valve control unit , and the ignition period control unit . The ECU sets a retard amount of the ignition period of the idle cylinder behind the basic ignition period at least in starting the all-cylinder operation in accordance with an amount of burned gas existing in the idle cylinder in switching to the all-cylinder operation from the reduced-cylinder operation.