Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Engine Ignition
The electronic ignition (EI) system is a coil-on-plug ignition system. The coil-on-plug ignition system consists of the following components:
- Ignition coil-on-plugs
- Spark plugs
- Crankshaft position (CKP) sensor
- Camshaft position (CMP) sensor
The ignition coil-on-plugs:
- change low voltage signals from the PCM to high-voltage pulses.
- supply the high-voltage pulses to the spark plugs.
- are connected directly to each spark plug.
- have replaceable coil boots (2.5L).
The spark plugs:
- change high-voltage pulses into a spark which ignites the fuel and air mixture.
The CKP sensor:
- is a variable reluctance sensor.
- is triggered by a 36-minus-1 tooth trigger wheel mounted on the crankshaft.
- provides base timing and crankshaft speed (RPM) to the PCM.
The CMP sensor (2.5L):
- is a variable reluctance sensor.
- provides camshaft rotational location information to the PCM.
The CMP sensor (3.0L):
- is a Hall-effect sensor.
- is mounted in the front cover.
- is triggered by the high point mark on the intake camshaft trigger wheel.
- provides camshaft rotational location information to the PCM.
NO RELATED
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.