Canister purge gas control device and control method for internal combustion engine

摘要

A fuel injection control device for an internal combustion engine includes a canister which temporarily collects fuel vapor purge gas generated in a fuel tank and a canister purge gas control system which introduces the collected fuel vapor purge gas into the internal combustion engine during the operation thereof. The canister purge gas control system includes a purge gas air/fuel ratio calculating system which determines the purge gas air/fuel ratio of the collected fuel vapor purge gas to be introduced into the combustion engine, and only during a time when the purge gas air/fuel ratio calculated by the purge gas air/fuel ratio calculating system is within a predetermined range, the canister purge gas control system interrupts the introduction of the collected fuel vapor purge gas into the internal combustion engine so as to permit an air/fuel ratio learning control system to perform an air/fuel ratio learning control, whereby an air/fuel ratio learning control is performed without causing an air/fuel ratio variation and an output power variation of the internal combustion engine.