Air/fuel ratio control system in internal combustion engine

摘要

The system is associated with an engine equipped with a carburetor and includes a fuel supply conduit and/or air supply conduit each opening at its one end into an intake pipe at a location downstream of the throttle valve, an electromagnetic valve for each conduit arranged to control a fluid flow through each conduit, an exhaust gas sensor disposed in the exhaust system, and a control circuit which operates the electromagnetic valve such that the feed rate of fuel or air through each conduit is varied to compensate for any deviation indicated by a signal from the sensor of the air/fuel ratio of an air-fuel mixture consumed in the combustion chamber from a predetermined ratio.