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Manifold Pressure/Vacuum Sensor: Description and Operation



Manifold Absolute Pressure (MAP) Sensor, Intake (turbocharged Engines Only, 2002-2004)







The manifold absolute pressure (MAP) sensor detects the pressure in the intake manifold downstream of the charge air cooler (CAC). The signal from the sensor is primarily used by the engine control module (ECM) to check that the correct boost pressure is reached. The boost pressure is governed by the turbocharger (TC) control valve.

The sensor, which is a piezo resistor, is grounded in the control module and supplied with 5 V from the control module.

The resistance in the sensor changes depending on the pressure in the intake manifold, giving a signal of 0-5 V. Low pressure results in low voltage, high pressure in high voltage.

The engine control module (ECM) can diagnose the manifold absolute pressure (MAP) sensor.

The signal can be read using VIDA.

The manifold absolute pressure (MAP) sensor is in the intake hose for the throttle body (TB).