Fuel injection control apparatus and fuel injection control method for internal combustion engine

摘要

An internal combustion engine includes an in-cylinder injection valve and an intake port injection valve. An ECU controls the fuel injection valves in a fuel injection mode that corresponds to an operational state of the engine. When deterioration of the combustion state is detected while the engine operational state is in a predetermined operational region where fuel is injected at least from the in-cylinder injection valve, the ECU switches the fuel injection mode such that the ratio of the amount of fuel injected from the in-cylinder injection valve to the entire amount of fuel supplied to the cylinder is decreased. As a result, the engine combustion state is prevented from deteriorating while suppressing noise generated in the fuel pressurizing and supplying system.