Electronic Ignition (EI) System Description: Notes

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The electronic ignition (EI) system is responsible for producing and controlling a high energy secondary spark. This spark is used to ignite the compressed air/fuel mixture at precisely the correct time. This provides optimal performance, fuel economy, and control of exhaust emissions. This ignition system consists of a separate ignition coil connected directly to each spark plug, known as coil on plug. These coil assemblies are located in the center of the camshaft cover. The driver modules within each coil assembly are commanded ON/OFF by the powertrain control module (PCM). The PCM primarily uses engine speed and position information from the crankshaft and camshaft position sensors to control the sequence, dwell, and timing of the spark. The EI system consists of the following components: