Control apparatus and control method for internal combustion engine

A control apparatus for an internal combustion engine comprising:

• a first air/fuel ratio detection device provided in a portion of an exhaust passageway of an internal combustion engine that has a plurality of cylinders, the portion being on an upstream side of an exhaust gas-controlling catalyst arranged in the exhaust passageway;
• a second air/fuel ratio detection device provided in a portion of the exhaust passageway on a downstream side of the exhaust gas-controlling catalyst;
• an air/fuel ratio feedback control device that executes an air/fuel ratio feedback control so that a first detected value based on output of the first air/fuel ratio detection device follows a first predetermined target value and so that a second detected value based on output of the second air/fuel ratio detection device follows a second predetermined target value that corresponds to the first predetermined target value during an initial state;
• an abnormality detection device configured to detect a variation abnormality in air/fuel ratio among the cylinders;
• and
• a change device that changes the second predetermined target value of the air/fuel ratio feedback control when the variation abnormality in the air/fuel ratio among the cylinders is detected by the abnormality detection device.