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Manifold Pressure/Vacuum Sensor: Testing and Inspection

Manifold Absolute Pressure (MAP) Sensor Inspection




1. Check sensor O-ring (1) for damage and deterioration. Replace as necessary.
2. Arrange 3 new 1.5 V batteries (2) in series and connect its positive terminal to "Vin" terminal of MAP sensor (1) and negative terminal to "Ground" terminal. Then check voltage between "Vout" and "Ground".

Also, check if voltage reduces when vacuum is slowly applied up to 400 mmHg by using vacuum pump (3). If check result is not satisfactory, replace manifold absolute pressure sensor.

CAUTION: As connection to wrong terminal will cause damage to manifold absolute pressure sensor, make absolutely sure to connect properly as shown in the figure.




MAP sensor output voltage (Vin voltage 4.5 - 5.5 V, ambient temp. 20 - 30 °C (68 - 86 °F))