Patent ID: 6273063
Filing Date: 2001-08-14
Classification: F02D

Abstract:
An apparatus for controlling idle rotation speed of an internal combustion engine equipped with a fuel vapor treatment unit constructed so as to adsorb and retain in a canister, fuel vapor generated in a fuel tank, and supply fuel purged from the canister to an engine intake system, said apparatus comprising:an idle detection device for detecting an idle operating condition of the engine;a purge judgment device for judging if purge is being performed;a first feedback device for computing at the time of said idle operating condition and purge stopped condition, a first operating amount for controlling an engine intake air quantity so that an idle rotation speed of the engine coincides with a target idle rotation speed, and controlling the engine intake air quantity based on said first operating amount; anda second feedback device for computing at the time of said idle operating condition and purge execution condition, a second operating amount for controlling an engine intake air quantity so that an idle rotation speed of the engine coincides with a target idle rotation speed, and controlling the engine intake air quantity based on said second operating amount.