System for controlling the ignition timing of an internal combustion engine

A system for controlling ignition timing of an internal combustion engine having at least two cylinders, a microprocessor and an ignition timing control device comprising:

• first sensing means for sensing operating conditions of the engine at steady state and for producing a steady state signal;
• second sensing means for sensing an acceleration state of the engine and for producing an acceleration state signal;
• a knock sensor for sensing engine knock in a cylinder selected from the cylinders and for producing a knock signal;
• first means for distinguishing the timing for determining ignition timing of the selected cylinder and for producing a control starting signal;
• second means responsive to the control starting signal, to the steady state signal, to the acceleration state signal and to the knock signal for selectively producing a first ignition timing correcting signal representing an ignition timing correcting quantity at a time for deciding the ignition timing in steady state and for producing a second ignition timing correcting signal for the acceleration state respectively;
• third means responsive to the first or second ignition timing correcting signal and for correcting the ignition timing of the selected cylinder;
• fourth means for storing the corrected ignition timing for deciding the ignition timing of the other cylinder.