Ignition System: Description and Operation
The Camshaft Position sensor (CMP sensor):
- senses a high spot on the left camshaft sprocket.
- provides camshaft timing input for the Powertrain Control Module (PCM).
The Crankshaft Position sensor (CKP sensor):
- is a variable reluctance sensor.
- senses a missing tooth on the crankshaft sprocket.
- generates a CKP signal that is sent to the powertrain control module which counts this signal for engine rpm.
The ignition coil:
- changes low voltage pulses from the powertrain control module to high voltage pulses.
- has two transformers.
The ignition wire carries high voltage pulses from the ignition coil to the spark plug.
The spark plug:
- changes the high voltage pulse into a spark which ignites the fuel and air mixture.
- originally equipped on the vehicle has a platinum-enhanced active electrode for long life. The active electrode is different for the LH and RH spark plugs.
The ignition system is:
- an electronic distributor less ignition system controlled by an electronic engine control integrated with the powertrain control module.
- set for base timing at 10 degrees Before Top Dead Center (BTDC) and is not adjustable.