Patent ID: 7568454

Claim:
An intake air amount control system for an internal combustion engine, which variably controls a cam phase of an intake cam shaft for opening and closing an intake valve, relative to a crankshaft by a variable cam phase mechanism, and variably controls a valve lift of the intake valve by a variable valve lift mechanism, to thereby control an amount of intake air drawn into a cylinder of the engine, comprising: target intake air amount-setting means for setting a target intake air amount to which the amount of intake air is to be controlled, according to a load parameter indicative of load on the engine; intake air amount-detecting means for detecting the amount of intake air; first control value-calculating means for calculating a first control value for use in feedback controlling one of the cam phase and the valve lift to converge toward one of a corresponding target cam phase and a target valve lift such that the detected intake air amount converges to the target intake air amount, wherein a rate at which one of the cam phase and the valve lift is controlled to converge toward one of the corresponding target cam phase and the target valve lift is higher than a rate at which the detected intake air amount is caused to converge to the target intake air amount; and second control value-calculating means for calculating a second control value for use in controlling the other of the cam phase and the valve lift based on the first control value calculated by said first control value-calculating means.