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 to each spark plug by a short secondary wire. The driver modules within each coil assembly are commanded ON/OFF by the engine control module (ECM). The ECM primarily uses engine speed and position information from the crankshaft and camshaft position (CMP) sensors to control the sequence, dwell, and timing of the spark event. The EI system consists of the following components: