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Manifold Pressure/Vacuum Sensor


Vacuum in Inches of Mercury MAP sensor Signal Voltage


.39 in Hg 4.90 V

3.34 in Hg 4.60 V

6.30 in Hg 3.60 V

9.25 in Hg 3.10 V

12.20 in Hg 2.60 V

15.15 in Hg 2.10 V

18.11 in Hg 1.60 V

21.06 in Hg 1.10 V

24.01 in Hg .60 V

26.97 in Hg .31 V


Condition Expected Output Voltage

High Vacuum (Idle/Deceleration) 0.5 to 1.5 volts

Medium Vacuum (Cruise/Slight Acceleration) 1.5 to 3.0 volts

Low Vacuum (Hard Acceleration/Mechanical Failure) 3.0 to 4.5 volts

NOTE: Any reading of 0 volts or over 5 volts indicates a problem in the MAP sensor circuit.