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Electronic Engine Controls




Electronic Engine Controls

The electronic engine controls consist of the following:

- Camshaft Position (CMP) sensor
- Catalyst Monitor Sensor (CMS)
- Crankshaft Position (CKP) sensor
- Cylinder Head Temperature (CHT) sensor
- Heated Oxygen Sensor (HO2S)
- Intake Manifold Runner Control (IMRC) actuator (6.8L [3V] only)
- Knock Sensor (KS)
- Mass Air Flow (MAF) sensor
- PCM
- Throttle Position (TP) sensor (serviceable on 6.8L [3V] only)
- Variable Camshaft Timing (VCT) variable force solenoid (6.2L [2V] only)

Camshaft Position (CMP) Sensor

The CMP sensor:

- sends the PCM a signal indicating camshaft position used for fuel synchronization and coil firing.

Crankshaft Position (CKP) Sensor

The CKP sensor:

- sends the PCM a signal indicating crankshaft position.
- is essential for calculating spark timing.

Cylinder Head Temperature (CHT) Sensor

The CHT sensor:

- is mounted into the front of the left cylinder head and is not connected to any coolant passages.
- sends a signal to the PCM indicating the cylinder head temperature.

Heated Oxygen Sensor (HO2S) and Catalyst Monitor Sensor (CMS)

The HO2S and CMS:

- have the ability to create a voltage signal dependent on exhaust oxygen content.
- provide feedback information to the PCM used to calculate fuel delivery.

Intake Manifold Runner Control (IMRC) actuator (6.8L [3V] only)

The air induction system improves engine performance by using the IMRC as follows:

- The intake manifold has 2 runners per cylinder, feeding each of the intake ports in the cylinder heads.
- The IMRC assemblies are located between the upper intake manifold and cylinder heads, providing 2 air passages for each cylinder.
- The valve plates are opened and closed by the IMRC electric actuator, which is controlled by the PCM.
- One air passage is always open and the other passage switches from closed to open by means of a valve plate.
- Below 1,500 rpm, this valve plate is closed to improve fuel economy and emissions.

Knock Sensor (KS)

The KS:

- is located in the intake valley of the cylinder block.
- sends a signal to the PCM indicating engine detonation.

Mass Air Flow (MAF) Sensor

The MAF sensor:

- sends the PCM a signal indicating mass airflow rate of air entering the engine.
- incorporates the Intake Air Temperature (IAT) sensor.

PCM

The PCM:

- accepts input from various engine sensors and generates output signals to control fuel injection, ignition and emissions.

Throttle Position (TP) Sensor (serviceable on 6.8L [3V] only)

The TP sensor:

- sends the PCM a signal indicating the throttle plate angle.
- is the main input to the PCM from the driver.

Variable Camshaft Timing (VCT) Variable Force Solenoid (6.2L [2V] only)

The VCT variable force solenoid:

- is an electronic solenoid that supplies force to actuate the VCT oil control valve. The PCM transmits a signal based on the engine speed and load, the solenoid will move the VCT oil control valve activating either the advance circuit, retard circuit or hold position. The camshaft is then repositioned in relation to crankshaft timing to allow for optimum engine performance with lower emissions and reduced fuel consumption.