Excuse me, where is the air pressure sensor usually installed in the car?

Behind the throttle, it is generally installed on the air inlet. High-end cars have air flow meters and intake pressure sensors. Specific location features: there is a rubber tube or copper tube, and the other end is an iron knot with two wires on it.

It connects the intake manifold with a vacuum tube. With the different engine speed load, it senses the change of vacuum degree in the intake manifold, and then converts it from the change of sensor internal resistance to a voltage signal for ECU to correct the fuel injection quantity and ignition timing angle.

In the EFI engine, the intake pressure sensor is used to detect the intake air volume, which is called D-type injection system (velocity density type). The intake pressure sensor indirectly detects the intake air volume, instead of directly detecting it like the intake air flow sensor. At the same time, it is also affected by many factors, so there are many differences in the detection and maintenance of intake flow sensor, and the faults caused by it also have their particularity.

The intake pressure sensor detects the absolute pressure of the intake manifold behind the throttle. It detects the change of absolute pressure in the manifold according to the engine speed and load, and then converts it into signal voltage and sends it to the ECU. The ECU controls the basic fuel injection quantity according to the signal voltage.