Ignition timing control method for internal combustion engines at idle

摘要

An ignition timing control method for an internal combustion engine, which controls the ignition timing of a mixture to be supplied to the engine in a feedback manner responsive to the difference between the actual engine speed and the desired idling speed. When it is determined that the engine is in a predetermined idling region and the engine temperature is above a predetermined value, the ignition timing is retarded by a predetermined amount, and the ignition timing thus retarded is corrected by a correction value calculated by multiplying the difference between the actual engine speed and the desired idling speed by a predetermined coefficient, to thereby control the ignition timing to the ignition timing value thus corrected. The ignition timing feedback control is inhibited when the voltage at a predetermined input terminal of a central processing unit is at a predetermined input level.