Self-diagnosis apparatus in a system for prevention of scattering of

Abstract

Disclosed is a self-diagnosis apparatus in a fuel evaporation gas scattering preventing system in an internal combustion engine. The apparatus comprises: a canister communicating with a fuel tank and containing therein an absorption material adapted to absorb a fuel evaporation gas in the fuel tank; a discharge path for making the canister communicate with a suction path of an internal combustion engine; an opening/closing device provided in the discharge path for opening/closing the discharge path; an air-fuel ratio detector for detecting an air-fuel ratio of an air-fuel mixture fed to the internal combustion engine; a gas generation quantity detector for detecting a quantity of generation of fuel evaporation gas within the fuel tank; judgment device for controlling the opening/closing device to close/open the discharge path to thereby judge whether abnormality exists or not on the basis of a change in the air-fuel ratio detected by the air-fuel ratio detector upon closing/opening discharge path, when the gas generation quantity detector detects that gas is being generated within the fuel tank; and a warning device for generating a warning when the judgment device proves existence of abnormality.