Tracer L4-116 1.9L SOHC (1991)
![background image](/mercury/tracer/l4-116_1.9l_sohc/Page-942001.png)
Ignition Coil: Description and Operation
Ignition Coil Pack
The ignition coil pack contains two separate ignition coils controlled by the EDIS module through two coil leads. Each ignition coil fires two spark
plugs simultaneously; one plug on the compression stroke and one on the exhaust stroke. On the next engine revolution the reverse occurs. The spark
plug fired on the exhaust stroke uses very little of the ignition coils stored energy. The Majority of energy is used by the spark plug on the compression
stroke. Since these two spark plugs are connected in series, the firing voltage of one plug will be negative with respect to ground, while voltage of the
other will be positive with respect to ground.