Air-Fuel Ratio Control System for Internal Combustion Engines

摘要

An air-fuel ratio control system for an internal combustion engine controls an amount of fuel supplied to the engine. Operating conditions of the engine, including engine rotational speed and intake pressure, are detected. Also detected is a valve opening of a recirculation control valve arranged in an exhaust recirculation passage, for controlling recirculation of exhaust gases. An amount of recirculation gas is determined based on a detected value of the valve opening of the recirculation control valve. A fuel supply amount is calculated based on the engine rotational speed and the intake pressure. The fuel supply amount is corrected based on the amount of recirculation gas determined.