Manifold absolute pressure (MAP) sensor

Fig 1: Identifying Manifold Absolute Pressure Sensor

Courtesy of VOLVO CARS OF NORTH AMERICA.

The manifold absolute pressure (MAP) sensor is on top of the radiator and is connected to the intake manifold by a hose.

The manifold absolute pressure (MAP) sensor detects quick pressure changes in the intake manifold after the throttle. The signal from the sensor is used by the engine control module (ECM) to supplement the mass air flow (MAF) sensor when calculating injection period.

The semi-conductor sensor is grounded in the control module and is supplied with power from the control module.

As the pressure in the intake manifold varies, the position of the silicone membrane in the sensor changes. This generates a signal to the engine control module (ECM). Low pressure produces low voltage, high pressure produces high voltage.

The engine control module (ECM) can diagnose the manifold absolute pressure (MAP) sensor. The sensor signal can be read using VIDA.