Rodeo S 2WD L4-2.2L (1999)
Manifold Absolute Pressure Sensor: Description and Operation
Manifold Absolute Pressure (MAP) Sensor
The manifold absolute pressure (MAP) sensor responds to changes in intake manifold pressure (vacuum). The MAP sensor signal voltage to the PCM
varies from below 2 volts at idle (high vacuum) to above 4 volts with the ignition ON, engine not running or at wide-open throttle (low vacuum).
The MAP sensor is used to determine the following:
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Manifold pressure changes while the linear EGR flow test diagnostic is being run. Refer to DTC P0401.
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Engine vacuum level for other diagnostics.
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Barometric pressure (BARO).
If the PCM detects a voltage that is lower than the possible range of the MAP sensor a DTC will be set.
A signal voltage higher than the possible range of the sensor will set a DTC.
An intermittent low or high voltage will set a DTC.
The PCM can detect a shifted MAP sensor.
The PCM compares the MAP sensor signal to a calculated MAP based on throttle position and various engine load factors. If the PCM detects a MAP
signal that varies excessively above or below the calculated value a DTC will set.
