July 1: So it begins. Don't worry, this is not in the correct legal jurisdiction!
BARO
Scan tool displays 10-105 kPa (0.0-5.00 volts). The barometric pressure reading is determined from the MAP sensor signal monitored during key-up and Wide-Open Throttle (WOT) conditions. Barometric pressure is used to adjust the fuel delivery and the spark advance in order to compensate for altitude changes.