FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Barometric Pressure Sensor: Description and Operation

PURPOSE
The Barometric Pressure (BARO) sensor detects changes in atmospheric pressure. This information is transferred to the Powertrain Control Module (PCM) by an input signal. The PCM calculates sensor input to optimize air/fuel ratio, idle speed, purge flow and A/C cutoff.

OPERATION
The BARO sensor is a frequency generating device producing varying signals depending on the amount of barometric (atmospheric) pressure.