Air/fuel ratio control apparatus

摘要

Fuel vapor is produced in a fuel tank and absorbed in a canister. The absorbed fuel vapor is purged through a purge passage into an engine induction passage under predetermined engine operating conditions. A purge valve is provided in the purge passage to regulate the supply of gaseous mixture, including the absorbed fuel vapor, into the engine. A purge rate factor is determined corresponding to the concentration of evaporated fuel in the gaseous mixture. The concentration is determined utilizing the temperature of the fuel in the fuel tank.