Basic Control

When starting, ECM controls ignition timing according to the engine speed and coolant temperature.
After the engine is started, ECM corrects the ignition timing according to the driving conditions (engine coolant temperature, accelerator pedal position, throttle position, control request from CVT etc.) based on the engine speed and fuel injection pulse width.
If knocking occurs, ECM retards the ignition timing within the anti-knocking control zone according to the knocking condition.
When the engine is idling, ECM controls the ignition timing to stabilize idling speed.
ECM controls the duration of power transmission (power transistor ON time) to ignition coil according to the engine speed and battery voltage.
When the engine idle speed or the ignition timing deviates from specified value, "Idle Air Volume Learning" is required.