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Manifold Pressure/Vacuum Sensor: Description and Operation




Manifold Absolute Pressure (MAP) Sensor







The manifold absolute pressure (MAP) sensor detects quick pressure changes in the intake manifold after the throttle. The signal from the sensor is used by the engine control module (ECM) as an addition to the mass air flow (MAF) sensor to calculate the injection period.

The semi-conductor sensor is grounded in the control module and is supplied with power from the control module.

The resistance in the sensor changes depending on the pressure in the intake manifold, giving a signal of 0.5-4.5 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 VADIS.

The manifold absolute pressure (MAP) sensor is on top of the radiator and is connected to the intake manifold by a hose.