Manifold Pressure/Vacuum Sensor: Description and Operation

Manifold Absolute Pressure Sensor:

The Manifold Absolute Pressure (MAP) sensor measures the pressure in the intake manifold and provides this information as a variable frequency signal to the Powertrain Control Module (PCM). With the Ignition Switch in the Key ON/Engine OFF position, the MAP sensor will indicate the barometric pressure in the intake manifold. The MAP sensor is used to indicate boost pressure on the diesel engine.