A control system which is capable of compensating for and suppressing the influence of a periodic disturbance on a controlled object more quickly, even when the controlled object is subjected to the periodic disturbance the amplitude of which periodically ...

In an internal combustion engine provided with a variable valve mechanism that varies a valve operating characteristic of an intake valve, the valve operating characteristic of the intake valve is detected, and a flow loss coefficient and an effective open...

A plurality of intake air amount control systems are provided for diagnosing a failure of each intake air amount control system. At the failure of any of them, a fail-safe control is performed using a normal intake air amount control system.

The method involves separately regulating air-fuel mixtures to cylinder banks, detecting signals representing the fuel quantity to be fed to each cylinder per stroke and/or detecting rough running values per cylinder and averaging to a bank mean value per ...

In an engine capable of continuously controlling an intake air quantity by varying an intake valve operating characteristic, an intake valve lift is sensed as well as an engine speed. Then, an intake air quantity is calculated in accordance with the engine...

In a method of and apparatus for continuously controlling a quantity of air drawn into an internal combustion engine by varying operating characteristics of an intake valve, a control unit uses avalve lift included in a range wherein the quantity of air is...

A combustion control system for a spark-ignition internal combustion engine includes a variable piston stroke characteristic mechanism changing a compression ratio of the engine, sensors detecting engine operating conditions, i.e., engine speed and engine ...