Viper V10-488 8.0L (1992)
Engine Control Module: Description and Operation
Modes of Operation
Acceleration
This is a CLOSED LOOP mode.
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The PCM recognizes an abrupt increase in throttle position or MAP pressure, as a demand for increased engine output to accelerate vehicle.
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The PCM increases injector pulse width, in response to increased fuel demand.
Cruise or Idle
This is a CLOSED LOOP mode.
At cruising speed, or idle, with the engine at operating temperature, the PCM receives inputs from:
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Air Conditioning Control Position
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Battery voltage
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Camshaft position (CMP) sensor
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Engine coolant temperature (ECT) sensor
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Manifold absolute pressure (MAP) sensor
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Intake air temperature (IAT) sensor
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Crankshaft position (CKP) sensor
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Throttle position sensor (TPS)
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Heated oxygen sensor (HO2S)
Based on these inputs the following occurs:
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The fuel injectors are fired by the PCM and ICM switching the ground path to control injection sequence and injector pulse width.
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The PCM monitors the oxygen sensor input and adjusts air/fuel ratio, adjusts engine idle speed, and controls ignition timing. The PCM adjusts
the air/fuel ratio by controlling the injector pulse width, adjusts the engine idle speed by controlling the automatic idle speed motor, and
adjusts the ignition timing through the ignition control module.
Deceleration
This is a CLOSED LOOP mode.
During deceleration the the PCM receives inputs from:
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Engine coolant temperature (ECT) Sensor
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Manifold absolute pressure (MAP) sensor
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Throttle position sensor (TPS)
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Crankshaft position (CKP) sensor
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Battery Voltage
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Air Conditioning Control position
Based on these inputs the PCM will:
