Manifold Absolute Pressure (MAP) Sensor

Turn ignition off. Locate MAP sensor on firewall. Unplug connector from sensor. Inspect wiring between sensor connector and ECM for shorts or open circuits. See WIRING DIAGRAMS article in the ENGINE PERFORMANCE Section. Repair as required.
Connect breakout box between ECM and vehicle harness. Turn ignition on. Measure voltage between ECM terminals No. 22 and 67. If voltage is not approximately 5.0 volts, temporarily substitute known good ECM. Retest system.
Turn ignition off. Connect vacuum/pressure pump and gauge to sensor. Turn ignition on. Measure voltage between ECM terminalsNo. 43 and 67 at pressures specified. See MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR VOLTAGE table. Replace sensor if voltage is not approximately as specified.

MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR VOLTAGE ⁽¹⁾

Pressure - In. Hg

Volts

-22.5

0.5

-15.0

0.9

1.8

7.5

2.3

15.0

2.8

22.5

3.3

⁽¹⁾	Measure voltage between terminals No. 1 and No. 2.