Evaporative emission control system for internal combustion engines

摘要

An evaporative emission control system for an internal combustion engine includes an evaporative fuel passage extending between the intake system and the fuel tank of the engine. A control valve is arranged across the evaporative fuel passage, for opening and closing the evaporative fuel passage. The opening of the control valve is controlled such that the interior of the fuel tank is under negative pressure during operation and stoppage of the engine.