Apparatus and method for controlling fuel injection in internal combustion engine

An electronic control unit computes a first correction value for compensating for the deviation of the actual air-fuel ratio in relation to a target air-fuel ratio when fuel is supplied to each combustion chamber from corresponding port injector and in-cylinder injector such that the ratio of the fuel injection amount of the port injector to the total fuel injection amount of the corresponding port injector and in-cylinder injector seeks a first distribution ratio. The electronic control unit also computes a second correction value for compensating for the deviation of the actual air-fuel ratio in relation to the target air-fuel ratio when fuel is supplied to each combustion chamber from the corresponding injectors such that the ratio of the fuel injection amount of the port injector to the total fuel injection amount of the corresponding injectors seeks a second distribution ratio that is different from the first distribution ratio. Further, the electromagnetic control valve corrects the fuel injection amount of each of the injectors based on the first and second distribution ratios and the first and second correction values.