2.0L Ignition System (Service Information): Description
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 ignition coil on plug. The system's four main components are the ignition coils, spark plugs, Camshaft Position (CMP) sensors, and the Crankshaft Position (CKP) sensor. Refer to SENSOR, CRANKSHAFT POSITION, DESCRIPTION . The ignition coil on plug ignition system utilizes an ignition coil for each cylinder. The ignition coils are mounted directly over the each spark plug.
The ignition system is a static, inductive discharge type with spark timing determined by the PCM and is not adjustable. The system includes two high tension double outlet coils in a single housing connected directly to the spark plugs. The PCM manages the basic ignition timing based on engine speed in Revolutions Per Minute (RPM) and Manifold Air Pressure (MAP). This ignition timing advance value is corrected depending on Engine Coolant Temperature (ECT) and Inlet Air Temperature (IAT). The spark plugs are connected to the secondary winding terminals of each respective coil by high tension cables. The ignition coils are mounted on top of the cylinder head cover.
CMP
The two CMP sensors are located in the rear quadrant of the engine, one on each side of the cylinder head assembly. The CMP sensor that is on the exhaust side is covered by a metallic heat shield for thermal protection. Each CMP sensor is inserted into a bore, has an O-ring seal to prevent leakage and is held in place by a bolt.
The CMP sensors are single element hall effect sensors mounted so that the target wheel associated with that camshaft may be sensed. This application uses ferrous targets on the camshafts.
Knock Sensor
The knock sensor is made of piezoelectric material. Depending on the vibration frequency of the cylinder walls caused by ignition, the sensor generates voltage proportional to it. The PCM detects the voltage value generated by the sensor its rate of change, and as a function of the latter, it can understand whether there is knocking in the cylinder. To reduce the pinging caused by knocking, the PCM starts reducing the ignition advance in order to limit the maximum pressure that can be reached in the combustion chamber. The higher the pressure, the greater the risk of spark knocking. The engine is equipped with two knock sensors located on the crankcase on the intake side near the intake manifold.
Variable Valve Timing
This engine is equipped with Variable Valve Timing (VVT). This system adjusts the timing of the intake and exhaust camshafts independently using solenoids and Oil Control Valves (OCV) to direct oil pressure into the camshaft phaser assemblies. The camshaft phaser assembly advances and retards camshaft timing to improve engine performance, mid-range torque, idle quality, fuel economy, and reduce emissions. The VVT solenoids are located on the front of the cylinder head cover. The pintle should move freely within the solenoid body. Do not attempt to disassemble the solenoids, they are not serviceable. The solenoids are identical but should be installed in the same location as removed.