Control system for internal combustion engines

摘要

A control system for an internal combustion engine controls a fuel injection amount based on operating conditions of the engine and an evaporative fuel concentration-dependent correction coefficient. The control system includes a purge control valve arranged in a purging passage connecting a canister for temporarily storing evaporative fuel generated from a fuel tank and an intake passage. This coefficient is held to a predetermined value for a predetermined time period after purging is permitted, and to another for a predetermined time period after purging is inhibited. In another aspect, the purge control valve is controlled based on operating conditions of the engine and a purging flow rate correction coefficient. This coefficient is held when purging is inhibited, and is progressively set to a larger value depending on the evaporative fuel-dependent correction coefficient, after purging is permitted. In another aspect, when a vehicle on which the engine is installed is started, the purge control valve is controlled based on a special purging control amount which is progressively increased based on a parameter related to a standing start of the vehicle. In another aspect, the operation of the purge control valve is inhibited for a predetermined time period after the engine has shifted from a purge control valve-disabling region to a purge control valve-enabling region.