Patent ID: 9206754
Filing Date: 2015-12-08
Classification: F02D

Abstract:
1. A control device of an internal combustion engine, the control device comprising: a first fuel injection valve and a second fuel injection valve which are provided in each of a plurality of cylinders of the internal combustion engine; and an electronic control unit operatively connected to the first fuel injection valve, the second fuel injection valve, and the internal combustion engine, the electronic control unit configured to: inject a predetermined fuel amount of fuel from the first fuel injection valve and the second fuel injection valve, by using an injection ratio which is set in accordance with an engine operation state; calculate a first value indicating a degree of variation in air-fuel ratios between the cylinders on the basis of a predetermined output of the internal combustion engine associated with the fuel injection from the first fuel injection valve and the second fuel injection valve by using a first predetermined injection ratio; calculate a second value indicating the degree of variation in the air-fuel ratios between the cylinders on the basis of a predetermined output of the internal combustion engine associated with the fuel injection from the first fuel injection valve and the second fuel injection valve by using a second predetermined injection ratio which is different from the first predetermined injection ratio; select one mode from a plurality of modes including a first mode relating to abnormality in at least any one of a plurality of first fuel injection valves and a second mode relating to abnormality in at least any one of a plurality of second fuel injection valves, on the basis of the first value and the second value; calculate a variation value indicating the degree of variation in the air-fuel ratios between the cylinders on the basis of the first value and the second value; and calculate the predetermined fuel amount while performing correction on the basis of the selected mode and the variation value so that the air-fuel ratio tracks a target air-fuel ratio in accordance with outputs of a catalyst upstream sensor and a catalyst downstream sensor which are provided on upstream and downstream sides of a catalyst in an exhaust passage and which respectively generate the outputs corresponding to an amount of oxygen in the exhaust gas, the first fuel injection valve and the second fuel injection valve inject the predetermined fuel amount corrected on the basis of the selected mode and the variation value.