Ignition Coil: Description and Operation

Ignition Coil:

The ignition coil is located inside the distributor. The distributor is mounted to the right end of the engine block behind the thermostat housing.

This engine uses an epoxy type coil. The coils are not oil filled. The windings are embedded in a heat and vibration resistant epoxy compound.

On this engine, The PCM controls ignition timing by turning on and off the transistor in the distributor.

By switching the ground path for the coil on and off, the PCM adjusts ignition timing to meet changing engine operating conditions.

The PCM operates the ignition coil through the Auto Shutdown (ASD) relay. When the relay is energized by the PCM, battery voltage is connected to the ignition coil positive terminal. The PCM will de-energize the ASD relay if it does not receive an input from the distributor pick-up. Refer to Auto Shutdown (ASD) Relay and Fuel Pump Relay.