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Ignition System: Description and Operation

The Electronic Ignition (EI-High Data Rate) system consists of the following components:

- Crankshaft Position (CKP) sensor
- Ignition coil
- Desired spark angle signal from the Powertrain Control Module (PCM)
- related wiring.

The signal generated from the crankshaft position sensor provides:

- Base timing, which is set at 10° BTDC and is not adjustable.
- Crankshaft speed (rpm).

The PCM uses this information to determine ignition coil turn ON and turn OFF time. A separate ignition control module is no longer used. This feature is built in to the PCM.