Method and system for controlling engine ignition timing

An ignition timing control method for an internal combustion engine, comprising:

• determining if predetermined conditions for ignition retardation control exist;
• calculating a basic ignition timing value based on a knocking learning value, an engine speed, an intake air pressure, and an intake air temperature, if it is determined that the predetermined conditions exist;
• calculating an ignition timing retardation value based on an engine speed and an intake air pressure;
• calculating an ignition retardation coefficient based on an engine coolant temperature;
• calculating a final ignition timing value based on the basic ignition timing value, the ignition timing retardation value, and the ignition retardation coefficient;
• and
• controlling ignition timing according to the final ignition timing value.

An ignition timing control system for an internal combustion engine, comprising:

• an ignition device;
• and
• a control unit configured for:
• receiving inputs of one or more vehicle operating conditions, determining an ignition timing value based on the vehicle operating conditions, and outputting a signal representative of the determined ignition timing value to the ignition device, where the control unit is programmed to execute steps comprising:
• determining if a predetermined condition for ignition timing retardation control exists;
• calculating a basic ignition timing value based on a knocking learning value, an engine speed, an intake air pressure, and an intake air temperature, if it is determined that the predetermined condition exist;
• calculating an ignition timing retardation value based on an engine speed and an intake air pressure;
• calculating an ignition retardation coefficient based on an engine coolant temperature;
• calculating a final ignition timing value based on the basic ignition timing value, the ignition timing retardation value, and the ignition retardation coefficient;
• and
• controlling ignition timing according to the final ignition timing value.