Manifold Absolute Pressure Sensor
The pressure 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) as a complement to other pressure sensors in the intake system to control throttle, as well as to calculate injection time and requested fuel pressure.
The air pressure sensor is located on the upper part of the intake manifold.
The sensor, which is an Piezo resistive resistor, is grounded in the control module and supplied with power (5 V) from the control module.
Depending on the pressure, the silicone membrane in the sensor moves which changes the resistance, and thus varies the voltage level of the analogue signal to the control module.
For information about electrical connection, see wiring diagram. For sensor characteristics and normal values, see signal specification and component specification.
The pressure sensor can be diagnosed by the Engine Control Module (ECM) and the sensor signal can be read off.