In an control apparatus and a control method for an internal combustion engine with a variable valve-characteristic mechanism that changes a valve characteristic that includes at least one of the duration and the maximum lift of an intake valve, the operating position of the mechanism is detected, and the mechanism is controlled so that a value of the valve characteristic corresponding to the operating position is equal to a target value corresponding to an engine operating state. After the target value is changed so that the intake valve opens/closes in accordance with a specific value of the valve characteristic, the operating position of the mechanism is learned as a reference position for the control of the valve characteristic. An intake-air-amount adjustment device upstream of the intake valve is controlled to offset the change in the amount of intake air caused by changing the target value when the reference position is learned.

 
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> Method to estimate variable valve performance degradation

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