Electronic Engine Controls
The electronic engine controls consist of the following:
- PCM
- Camshaft Position (CMP) sensor (2 required)
- Clutch Pedal Position (CPP) switch (manual transmission only)
- Crankshaft Position (CKP) sensor
- Mass Air Flow (MAF) sensor
- Heated Oxygen Sensor (HO2S)
- Catalyst Monitor Sensor (CMS)
- Knock Sensor (KS) (2 required)
- Engine Coolant Temperature (ECT) sensor
- Variable Camshaft Timing (VCT) oil control solenoid (2 required)
The PCM:
- accepts input from various engine sensors and generates output signals to control fuel injection, ignition and emissions.
The CMP sensor:
- sends the PCM a signal indicating camshaft position used for fuel synchronization.
The CPP sensor:
- sends a signal through the instrument cluster to the PCM. The PCM needs this signal to improve engine running performance during gear changes.
The CKP sensor:
- sends the PCM a signal indicating crankshaft position.
The MAF sensor:
- uses a hot-film element to measure the amount of air entering the engine.
The HO2S :
- creates a voltage signal dependent on exhaust oxygen content.
- provides feedback information to the PCM used to calculate fuel delivery.
The CMS :
- monitors oxygen content after it flows through the catalytic converter.
- provides a voltage to the PCM used to calculate catalytic converter integrity.
The KS :
- is used to detect engine detonation.
- sends a voltage signal to the PCM.
The ECT sensor:
- sends the PCM a signal indicating engine coolant temperature.
- voltage decreases as coolant temperature increases.
The VCT oil control solenoid:
- is an electronic solenoid that actuates the flow of oil to the variable camshaft. Once the PCM transmits a signal, the solenoid moves a valve spool, directing oil into the camshaft phaser cavity. This action changes valve timing by either inducing an advance or retard condition. The camshaft is, thereby repositioned in relation to crankshaft timing and allows for optimum engine performance and lower emissions
Refer to the INTRODUCTION - GASOLINE MODELS for additional information on electronic engine control components.