Manifold Absolute Pressure (Map) Sensor
MAP sensor is located to right center of firewall. With ignition on, backprobe terminal "A22" of control unit. Voltmeter should indicate 2.5-4.4 volts, depending upon altitude. This is a barometric pressure reading. Start engine. Voltmeter should read 2.3-3.8 volts, depending upon altitude and vacuum present at sensor. This is an absolute pressure reading. For complete pressure/vacuum/voltage relationship, see SENSOR RANGE CHARTS article in this section.