Engine Ignition
WARNING: This page is about a different car, the 2004 Mercury Mountaineer and 2004 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.
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) is 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.
- has 3 transformers.
- fires 2 spark plugs simultaneously.
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.