Electronic Engine Controls

The electronic engine controls consist of the following:
^ Powertrain Control Module (PCM)
^ Throttle Position (TP) sensor
^ Idle Air Control (IAC) valve
^ Cylinder Head Temperature (CHT) sensor
^ Camshaft Position (CMP) sensor
^ Crankshaft Position (CKP) sensor
^ Mass Air Flow (MAF) sensor
^ Intake Air Temperature (IAT) sensor
^ Heated Oxygen Sensor (HO2S)
^ catalyst monitor sensor
^ Knock Sensor (KS)
^ Clutch Pedal Position (CPP) switch

The PCM needs the following inputs to calibrate the engine correctly:
^ crankshaft position
^ camshaft position
^ engine rpm
^ engine load
^ engine coolant temperature
^ mass air flow
^ amount of engine detonation

The TP sensor:
^ sends the PCM a signal indicating throttle plate angle.
^ is the main input to the PCM from the driver.
^ is not repaired separately from the throttle body.

The IAC valve:
^ controls bypass air around the throttle plate at low speeds.
^ is controlled be the PCM.

The ECT sensor:
^ sends the PCM a signal indicating engine temperature.
^ resistance decreases as coolant temperature increases.

The CHT sensor:
^ sends the PCM a signal indicating the cylinder head temperature.
^ resistance decreases as coolant temperature increases.

The CMP sensor:
^ sends the PCM a signal indicating camshaft position used for fuel synchronization.

The CKP sensor:
^ sends the PCM a signal indicating crankshaft position.
^ is essential for calculating spark timing.

The MAF sensor:
^ sends the PCM a signal indicating mass air flow rate of air entering the engine.

The IAT sensor:
^ sends the PCM a signal indicating the temperature of the air entering the engine.
^ is incorporated into the MAF sensor and is repaired as an assembly.

The HO2S:
^ has the ability to create a voltage signal dependent on exhaust oxygen content.
^ provides feedback information to the PCM used to calculate fuel delivery.

The catalyst monitor sensor:
^ monitors oxygen content after it flows through the catalytic converter.
^ provides a voltage to the PCM used to calculate catalytic converter integrity.

The PSP switch:
^ sends a signal to the PCM to increase idle speed for engine stability when power steering pump pressure increases above a set pressure value.

The KS:
^ sends a signal to the PCM indicating engine detonation, which retards the ignition timing as necessary.

The CPP switch:
^ is mounted on the clutch pedal bracket.
^ sends a signal to the speed control amplifier to disengage the speed control system when the clutch pedal is depressed.