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Manifold Pressure/Vacuum Sensor: Testing and Inspection

SCAN TOOL DIAGNOSIS
The Tech 1 scanner (or equivalent) displays manifold pressure and will display volts and kPa of pressure. Key "ON," engine stopped (no vacuum), Manifold Absolute Pressure (MAP) will display high voltage or pressure, while at idle (high vacuum), MAP will display low voltage or pressure. On acceleration MAP will display high and on deceleration will display low voltage. A failure in the MAP sensor circuit should result in a Diagnostic Trouble Code (DTC) 33 or DTC 34.