FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Ignition Timing: Description and Operation

Ignition timing is determined by the powertrain control module in response to engine operating conditions based on stored data tables or maps.Once ignition tuning has been determined, the powertrain control module interrupts the current to the primary circuit of the ignition coil thus triggering the ignition spark which is supplied to the cylinders through the spark plug wires and spark plugs.