What is an Intake Manifold Absolute Pressure Sensor?

[Morales]

An intake manifold absolute pressure sensor is a device that detects the absolute pressure in the intake manifold behind the throttle. It connects to the intake manifold via a vacuum tube and senses the vacuum changes inside the intake manifold as the engine operates under different speeds and loads. The sensor then converts the changes in internal resistance into a voltage signal, which the ECU uses to adjust fuel injection volume and ignition timing. The intake manifold absolute pressure sensor detects variations in absolute pressure within the manifold based on engine speed and load, converts this into a signal voltage, and sends it to the engine control unit (ECU). The ECU then uses this signal voltage to determine the basic fuel injection volume.