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Ignition Coil: Description and Operation





OPERATION
When one spark plug activates on the compression stroke, the companion spark plug activates on the exhaust stroke. During the next engine revolution, the reverse will occur. The majority of the ignition coils' energy is used by the spark plug which activates on the compression stroke, while the spark plug which activates on the exhaust stroke uses very little energy.

FEATURES
The ignition coil pack contains two separate ignition coils which are controlled by the Ignition Control Module (ICM) through two ignition coil leads. Each ignition coil activates spark plugs to two cylinders simultaneously.Since these two spark plugs are connected in series, the firing voltage of one spark plug is negative with respect to ground, while the voltage of the other is positive with respect to ground.