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Manifold Pressure/Vacuum Sensor: Description and Operation

MAP Sensor Cutaway/Voltage Output Characteristics:






The Manifold Absolute Pressure Sensor, is a silicon diaphragm strain gauge type of sensor. It converts a pressure differential to a voltage signal which is then sent to the ECU as an input. At idle with a manifold pressure of 500 mmHg (20 in.Hg) the sensor output is approx. 1.0 - 1.25 volts, at wide open throttle manifold pressure of 0 mmHg (0 in.Hg) the output is approx. 2.75 - 3.0 volts.