HOLDEN GEN III V8, Обучение по обслуживанию

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GEN III V8 ENGINE MANAGEMENT
INTAKE AIR TEMPERATURE SENSOR
The Intake Air Temperature (IAT) sensor is a
thermistor, (a resistor that changes resistance with
changes in temperature) mounted in the air cleaner
housing Of the intake system. Low intake air
temperature produces high resistance in the
sensor, approximately 1 0 1 k ohms at -40°C, while
high intake air temperature causes low sensor
resistance, approximately 80 ohms at 130°C.
The PCM:
1. Supplies a 5 volt signal voltage to the sensor
through a resistor in the PCM, and
2. Monitors the intake air temperature circuit
voltage, which will change when connected to
the intake air temperature sensor.
The circuit voltage will vary depending on the
resistance of the IAT sensor. The voltage will be
close to the 5 volt level when the sensor is cold,
and will decrease as the sensor warms.
The IAT sensor signal voltage is used by the PCM
to assist in calculating the fuel injector pulse width,
idle speed, canister purge and electronic spark
timing.
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