Engine Ignition
The ignition system consists of the following:
- Crankshaft position (CKP) sensor
- Ignition coil
- Spark plug wire
- Spark plug
The ignition system is:
- an electronic distributorless ignition system (EDIS).
- controlled by an electronic engine control integrated into the powertrain control module (PCM).
- set at 10 degrees before top dead center (BTDC) for base timing and is not adjustable.
The crankshaft position (CKP) sensor:
- is a variable reluctance sensor.
- senses a missing tooth on the crankshaft damper pulse ring.
- generates a crankshaft position signal which is sent to the PCM. The PCM counts this signal for engine rpm.
The ignition coil:
- changes low-voltage pulses from the PCM to high-voltage pulses.
- fires 2 spark plugs simultaneously.
- has 3 transformers.
- one transformer fires the spark plugs for cylinders 1 and 5
- one transformer fires the spark plugs for cylinders 2 and 6
- one transformer fires the spark plugs for cylinders 3 and 4
Spark plug wires carry high-voltage pulses from the ignition coil to the spark plugs.
The spark plugs:
- change high-voltage pulses to spark at the gap, which ignites the fuel and air mixture.
The firing order is: 1-4-2-5-3-6.