Throttle valve control system for an internal combustion engine

摘要

A throttle valve control system for an internal combustion engine sets a target manifold pressure for attaining a minimum fuel consumption rate in response to a detected engine rotational speed, and drives the throttle valve to a control opening determined so as to reduce the difference between the detected actual manifold pressure and the target manifold pressure. According to another feature, the system detects the operation position of the accelerator pedal and the throttle valve is driven to a control opening which is determined in accordance with the operation position of the accelerator pedal or the rate of change in the operation position of the accelerator pedal when the operation position or the rate of change in the operation position exceeds a predetermined value, respectively.