Ignition Timing Control: Notes

A microcomputer in the ECU controls the ignition timing according to engine speed and vacuum pressure in the intake manifold. Engine speed and vacuum pressure are transmitted to ECU by signals from crank sensor, cylinder (CYL) sensor, TDC sensor (Integra and Vigor), throttle angle sensor, coolant temperature sensor, knock sensor(s), and MAP sensor.

The ECU contains memory for ignition timing at various engine speeds, manifold pressure and coolant temperature. When these conditions have been processed, ECU sends signals to ignitor unit to control ignition timing.