Abstract: Disclosed is a method for controlling the quantity of intake air supplied to an internal combustion engine, in which the position of a valve member of a flow control valve having a non-linear valve opening characteristic is converted into an intake air quantity or a virtual valve position proportional to the intake air quantity so as to linearize the non-linear valve opening characteristic of the flow control valve. Application of the method of the present invention to an idle speed control device in an engine equipped with an electronic controlled fuel injection system is advantageous in that the quantity of intake air supplied to the engine can be accurately controlled under various operating conditions of the engine, therely preventing rotation of the engine at an excessively high speed and stalling of the engine, improving the fuel consumption and reducing noise generated from the engine.

Abstract: A first speed detecting means detects whether the engine speed has fallen below a prescribed level. A second speed detecting means detects whether an accelerator pedal angle has been changed at a speed higher than a predetermined value. A third speed detecting means is provided to detect whether the speed of the automobile is equal to, or higher than, a predetermined value. Upon receipt of the output signals from the first, second and third speed detecting means, a solenoid drive circuit drives engine vibration absorbers for a predetermined period of time. More specifically, the circuit energizes solenoids for this period. The solenoids rotate the thus rotary valves of the absorbers, thus closing the orifices of the absorbers. As a result, the absorbers generate great forces damping the back-and-forth motion of the engine. The vibrations of the engine are therefore not transmitted to the chassis of the automobile.

Abstract: When detecting means detects that changes have been achieved by an automatic transmission in lever position and/or gear position, a solenoid drive circuit is actuated for a predetermined period of time to drive shock absorbers which control the rolling of the engine of an automobile. More specifically, when it is actuated, the solenoid drive circuit energizes solenoids, whereby the rotary valves of the shock absorbers are rotated for said period. As a result, one of the two orifices of either shock absorber is closed, thus increasing the force damping the vibrations of the engine. Hence, the vibrations caused by a large torque of the engine are not transmitted to the chassis of the automobile.