Patent ID: 7891335

Claim:
A control system for an internal combustion engine having a plurality of cylinders and a cylinder halting mechanism for halting operation of at least one of said plurality of cylinders by stopping operation of at least one intake valve of said at least one cylinder, said control system comprising: operation control means for increasing a number of operating cylinders in an idling condition of said engine, and continuing the idling operation of said engine after the increase in the number of operating cylinders; an intake air control valve for controlling an amount of air supplied to said engine, said intake air control valve being a throttle valve disposed upstream of said at least one intake valve; and intake air amount control means for changing an opening of said intake air control valve when said operation control means increases the number of operating cylinders, wherein said intake air amount control means comprises switching means for switching a basic opening of said intake air control valve from a first basic opening corresponding to the number of operating cylinders before the increase in the number of operating cylinders to a second basic opening corresponding to the number of operating cylinders after the increase in the number of the operating cylinders, the second basic opening being greater than the first basic opening; and correcting means for correcting the basic opening in the closing direction during a predetermined time period when increasing the number of operating cylinders, wherein said correcting means sets a correction amount for correcting the basic opening in the decreasing direction to a predetermined amount at the same time said switching means switches the basic opening, and thereafter gradually decreases the correction amount.