Manifold Pressure/Vacuum Sensor: Description and Operation

PURPOSE
The Manifold Absolute Pressure (MAP) Sensor detects engine load by sensing intake manifold pressure. The Engine Control module (ECM) uses the sensor input to provide proper compensation for acceleration and periods of high load.

OPERATION



A 5 volt power supply is fed to the sensor whenever the ignition is turned ON. As pressures (vacuum) are detected, a signal (approx. 1 - 4 volts) is returned to the ECM. The ECM uses this information to determine engine load.