Manifold Pressure/Vacuum Sensor: Description and Operation

MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR-PCM INPUT
The MAP sensor reacts to absolute pressure in the intake manifold. It provides an input voltage to the Powertrain Control Module (PCM). As engine Toad changes, manifold pressure varies. The change in manifold pressure causes MAP sensor voltage to change. The change in MAP sensor voltage results in a different input voltage to the PCM. The input voltage level supplies the PCM with information about ambient barometric pressure during engine load while the engine is running. The PCM uses this input along with inputs from other sensors to adjust air-fuel mixture.

The MAP sensor is mounted on the side of the engine throttle body. The sensor is connected to the throttle body with a rubber L-shaped fitting.