System for controlling valve timing in event of failure

摘要

A valve timing control apparatus for an internal combustion engine is provided which is designed to ensure the drivability of the engine in the event of failure in operation of a variable valve timing control system made up of intake and exhaust side variable valve timing control mechanisms. If one of intake and exhaust side variable valve timing control mechanism has failed, the control apparatus actuates the other variable valve timing control mechanism to control the timing of opening and closing of a corresponding one of intake and exhaust valves so as to decrease an amount of overlap between the opening and closing of the intake and exhaust valves.