Barometric Pressure Sensor: Description and Operation

Manifold Absolute Pressure (MAP) Sensor/Barometric Read Solenoid:

The Single Board Engine Controller (SBEC) controls the barometric read solenoid. The solenoid is located in the Manifold Absolute Pressure (MAP) vacuum line, near the MAP sensor. The solenoid controls whether manifold pressure or atmospheric pressure is applied to the MAP sensor. Atmospheric pressure is applied periodically to measure barometric pressure. This happens once per throttle closure, but no more often than once in a three minute time period and within a specific rpm range. The main purpose for this input is to control turbo boost.