CONTROL APPARATUS AND CONTROL METHOD FOR INTERNAL COMBUSTION ENGINE

A control apparatus for an internal combustion engine includes at least one air-fuel ratio detection unit; a feedback control unit configured to determine a fuel injection amount for each of cylinders by performing air-fuel ratio feedback control using a feedback control amount; a learning unit configured to learn the feedback control amount so as to obtain a learned value, and to update the learned value at an update rate; an estimation unit configured to estimate a degree of imbalance in the air-fuel ratio among the cylinders based on a detected air-fuel ratio; an initialization unit configured to initialize the learned value when a deviation between the estimated degree of imbalance and a previous value is equal to or greater than a predetermined value; and an update rate change unit configured to increase the update rate, relative to a standard value after initialization of the learned value.