Manifold Absolute Pressure/Barometric Pressure Sensor & Solenoid

This combination Manifold Absolute Pressure/Barometric Pressure (MAP/BARO) sensor alternately senses engine vacuum and ambient air pressure. When solenoid is on, MAP/BARO sensor is sensing Barometric Pressure (BARO). When solenoid is off, MAP/BARO sensor is sensing Manifold Air Pressure (MAP). PCM uses these signals to control EVAP operation.