Patent ID: 6655357
Filing Date: 2003-12-02
Classification: F02D,Y02T

Abstract:
An abnormality detecting apparatus for an intake system of an internal combustion engine, which detects an abnormality of said intake system, said intake system having a throttle valve, a bypass passage bypassing said throttle valve, and an idling control valve for controlling the amount of air supplied through the bypass passage to said engine, said abnormality detecting apparatus comprising:first means for calculating a total intake air amount supplied to said engine; second means for calculating an amount of intake air supplied through said bypass passage based on a valve opening control quantity for said idling control valve; third means for calculating a parameter indicative of a leak air amount of said intake system according to the result of a comparison between the total intake air amount calculated by said first means and the amount of intake air calculated by said second means; and abnormality determining means for determining that said intake system is abnormal when the parameter calculated by said third means is greater than a determination threshold in an engine operating condition where said throttle valve is substantially fully closed.