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General Descritpion

The electronic ignition system on both Single Overhead Cam (SOHC) and Dual Overhead Cam (DOHC) engines provides spark energy to ignite the air/fuel mixture necessary for combustion. The powertrain control module (PCM) controls spark under all engine running conditions. The system components include: the PCM, Electronic Ignition (EI) module/coil pack, spark plugs, spark plug wires and knock sensor.

The spark dwell (On-time) and degrees of spark advance are dependant upon engine speed, Manifold Absolute Pressure ([1][2]MAP), and Engine Coolant Temperature (ECT). The PCM can vary spark advance from 39 ° BTDC to 3 ° ATDC under all engine running conditions when no spark knock is present.