Operation CHARM: Car repair manuals for everyone.

Ignition System Overview

The electronic ignition system controls the fuel combustion by providing a spark to ignite the compressed air/fuel mixture at the correct time. To provide the optimum engine performance, fuel economy, and control of exhaust emissions, the PCM controls the ignition system. The electronic ignition system has the following advantages over a mechanical distributor system:
^ No moving parts
^ Less maintenance
^ Remote mounting capability
^ No mechanical load on the engine
^ More coil cool down time between firing events
^ The elimination of mechanical timing adjustments
^ An increased available ignition coil saturation time

The electronic ignition system does not use the conventional distributor and coil. The ignition system consists of the following components and circuits:
^ The 6 ignition coils
^ The six ignition control (IC) circuits
^ The 2 ignition control modules (one per cylinder bank)
^ A Camshaft Position (CMP) sensor
^ A Crankshaft Position (CKP) sensor
^ The related connecting wires
^ The Powertrain Control Module (PCM)