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Ignition Control

DESCRIPTION AND OPERATION
The ignition control (IC) spark timing is the [1][2]PCM's method of controlling the spark advance and the ignition dwell.

The IC spark advance and the ignition dwell are calculated by the [1][2]PCM using the following inputs:
- Engine speed.
- Crankshaft position (58X reference).
- Camshaft position (CMP) sensor.
- Engine coolant temperature (ECT) sensor.
- Throttle position (TP) sensor.
- Knock signal (knock sensor).
- Park/Neutral position ((PRNDL input).
- Vehicle speed (vehicle speed sensor).
- Powertrain Control Module ([1][2]PCM) and ignition system supply voltage.