Ignition System: Description and Operation
IGNITION CONTROLDESCRIPTION
NOTE: All engines use a fixed ignition timing system. Basic ignition timing is not adjustable. All spark advance is determined by the Powertrain Control Module (PCM).
The ignition system used on these engines is referred to as the Direct Ignition System (DIS). The system's four main components are the coils, crankshaft position sensor, spark plugs, and camshaft position sensor. If equipped with the coil on plug ignition system it utilizes an ignition coil for every cylinder and is mounted directly over the each spark plug.
OPERATION
The crankshaft position sensor and camshaft position sensor are hall effect devices. The camshaft position sensor and crankshaft position sensor generate pulses that are inputs to the PCM. The PCM determines engine position from these sensors. The PCM calculates injector sequence and ignition timing from crankshaft & camshaft position. For a description of both sensors, refer to Camshaft Position Sensor and Crankshaft Position Sensor.