SYSTEM MONITORING METHOD AND DEVICE FOR CONTROLLING INTERNAL COMBUSTION ENGINE

PROBLEM TO BE SOLVED: To perform the simple monitoring and examining of a throttle valve, particularly in an engine brake operating condition, by detecting a parameter characterizing the air quantity, and judging the error when the parameter is over a threshold value. SOLUTION: The quantity of new air sucked by a throttle valve adjusting unit 130 which controls a throttle valve 131, is variable. The mass and/or volume MLI of the new air to be supplied, is detected by a sensor 135. The sensor 135 detects, for example, the air mass MLI while depending on the practical configuration. When the air mass MLI is lower than the threshold value, the throttle valve test is completed, and the throttle valve is proceeded to a normal state. When the air mass MLI is higher than the threshold value, the throttle valve is proceeded to a throttle valve temporary failure state. The test interrupting state is proceeded when an engine brake operating condition is not satisfied, or the error is generated during the testing period.