Manifold Pressure/Vacuum Sensor: Testing and Inspection

1. Check vacuum passage on intake manifold, sensor air vent hole and vacuum passage for clog. Clean if clogged.

CAUTION: Do not put wires into air vent hole for cleaning. It causes damage in sensor.

2. Check sensor O-ring for damage and deterioration. Replace as necessary.




3. Arrange 3 new 1.5 V batteries in series and connect its positive terminal to "Vin" terminal of coupler 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.

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




Output voltage (when Vin voltage is about 4.5 V)
If check result is not satisfactory, replace manifold differential pressure sensor.