Manifold Pressure/Vacuum Sensor: Description and Operation

MAP Sensor Service:

DESCRIPTION
The Manifold Absolute Pressure (MAP) sensor (5) 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 key on, engine not running or at wide open throttle (low vacuum).

OPERATION
The MAP sensor (5) is used to determine manifold pressure changes while the linear EGR flow test diagnostic is being run (refer to DTC P0401), to determine engine vacuum level for other diagnostics and to determine barometric pressure (BARO).