General System Description

Description:

DESCRIPTION
The Powertrain Control Module (PCM) controls the ignition timing in this ignition system. The PCM receives signals indicating engine status (engine speed, manifold vacuum, Engine Coolant Temperature [ECT], etc.) and selects the most appropriate ignition timing adjustments from its programming.

OPERATION
The PCM sends a signal to the Ignition Control Module (igniter) which is connected to the negative side of the ignition coil's primary circuit. When this signal is interrupted, the field around the primary coil collapses and a high voltage is induced in the secondary coil. The high voltage induced in the secondary coil is then forced to find a ground through the secondary (coil) wire, distributor cap, rotor, secondary (spark plug) wires and across the spark plug gap to the engine block.