Manifold Pressure/Vacuum Sensor: Description and Operation

ENGINE CONTROL COMPONENTS

Manifold Absolute Pressure (MAP) Sensor
The MAP sensor is a variable capacitor sensor that is supplied a 5-volt reference signal by the powertrain control module (PCM) and returns a voltage signal to the PCM relative to the intake manifold pressure. The sensor voltage increases as the pressure increases. The MAP sensor allows the PCM to determine the engine boost to calculate fuel quantity. In addition, the MAP sensor signal is used by the PCM for EGR system calculations and control.