Electronic control system for internal combustion engine

摘要

An electronic control system for an internal combustion engine, in which parameters necessary for the engine control are found by use of auxiliary quantities to thereby control the operating characteristic quantities of the internal combustion engine, the electronic control system comprising: a memory device for storing in advance, in the form of a two-dimensional map, a charging efficiency per se or related values of the charging efficiency corresponding to a degree of opening of the throttle valve and a number of engine revolution under the reference atmospheric condition; and a computing device for computing atmospheric pressure related values which include therein at least the atmospheric pressure value and are dependent on the atmospheric pressure, in accordance with a predetermined computation equation which takes a ratio of the charging efficiency per se or related values of the charging efficiency to be found out by selective use of signals of the intake air flow rate and a number of revolution of the internal combustion engine.