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Manifold Pressure/Vacuum Sensor: Description and Operation

MAP Sensor:





PURPOSE
Determines intake air flow volume.

LOCATION
On the firewall, near the wiper motor.

OPERATION
The sensor measures the air pressure within the intake manifold. The voltage signal provided to the ECU from the sensor will rise in proportion to the reise in manifold pressure (reduction of vacuum). This signal is used by the ECU to determine ignition timing and injector pulse width.