Patent ID: 6609059
Filing Date: 2003-08-19
Classification: F02B,F02D,F02M

Abstract:
A control system for controlling an internal combustion engine having an exhaust passage and an intake passage, said control system comprising:an exhaust gas recirculation mechanism having an exhaust gas recirculation passage connected between said exhaust passage and said intake passage, and an exhaust gas recirculation valve provided in said exhaust gas recirculation passage for controlling an exhaust gas amount to be recirculated from said exhaust passage through said exhaust gas recirculation passage to said intake passage; control means for calculating at least one control parameter of said engine based upon operating conditions of said engine including an open/closed condition of said exhaust gas recirculation valve and for controlling said engine using the calculated at least one control parameter; fuel supply interrupting means for interrupting the supply of fuel to said engine in a decelerating operation of said engine; pressure detecting means for detecting the intake pressure in said intake passage; pressure change calculating means for calculating the amount of change in the intake pressure between when opening said exhaust gas recirculation valve and when closing said exhaust gas recirculation valve, during a fuel-cut operation when the fuel supply to said engine is interrupted by said fuel supply interrupting means; and abnormality determining means for determining the abnormality of said exhaust gas recirculation mechanism based upon the amount of change in said intake pressure; said control means controlling said engine using a parameter of said at least one control parameter which is suitable for a closed condition of said exhaust gas recirculation valve during a predetermined time period from the time of first opening of said exhaust gas recirculation valve after finishing the abnormality determination by said abnormality determining means.