EZL Ignition Operation: Notes

The ignition control module stores a number of ignition characteristics for typical engine load speed ranges, idle speed ignition, and full load ignition characteristics. The ignition timing is selected from values stored in the control module based on input regarding intake manifold vacuum, coolant temperature, engine speed and throttle valve position.

Activation of the electronic ignition system is by the position indicator, which senses 3 segments on the flywheel/flexplate which are offset 120°. The ignition control module recognizes the segment front edge as a negative signal and the rear edge as a positive signal.

When starting the engine, the ignition timing is fixed up to about 270 RPM through the rear edge of the segments. The transition from the fixed ignition timing to the computed timing (corresponding to operating conditions at the moment) takes place above 270 RPM.

The intake manifold vacuum sensor in the ignition control module senses the momentary load condition of the engine and makes the necessary adjustments. During warm-up, different ignition characteristics are blocked, depending on coolant temperature.