Impco HHI, Руководство по обслуживанию

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determine engine load (the vacuum drops
when the engine is under load or at wide
open throttle). When the engine is under load,
the computer may alter the fuel mixture to im-
prove performance and emissions.
2) The intake air temperature or IAT sensor is a
variable resistance thermistor located in the air
intake passage which measures the tempera-
ture of the incoming air. The ECM uses the
resistance value to monitor incoming air tem-
perature and calculate the engine’s airflow
requirement. The ECM provides a voltage di-
vider circuit so that when the air is cool, the
signal reads a higher voltage, and lower when
warm. On cold starts, the ECM richens the
fuel/air mixture.
COOLANT TEMPERATURE SENSOR
The Engine Coolant Temperature sensor or ECT
is a variable resistance thermistor that changes
resistance as the engine's coolant temperature
changes. The sensor's output is monitored by the
ECM to determine a cold start condition and to
regulate various fuel and emission control func-
tions via a closed loop emission system.
OIL PRESSURE SENSOR
The Engine Oil Pressure Sensor is designed to
ensure adequate lubrication throughout the en-
gine. It provides a pressure value for the oil that
is monitored by the ECM. If the pressure drops,
a DTC will occur and the engine will shut down.