Forester S F4-2.5L DOHC (1998)
Ignition Coil: Description and Operation
Purpose and Operation
PURPOSE/OPERATION
Transforms battery voltage into ignition voltage and delivers it in the form of a high voltage surge to the secondary ignition components. When
current flow in the primary winding is stopped (by the ignitor), the collapse of the magnetic field causes a voltage to be induced in the secondary
windings. Voltage flows out of the coil's (2) secondary terminal, through the ignition cable, into the spark plug and jumps the electrode gap to
ground causing a spark. The coil fires two cylinders simultaneously; one on the power stroke and one on the exhaust stroke.
