Automobile parts for Dongfeng Cummins intake pressure sensor 4921322

Manifold Absolute Pressure Sensor (MAP).

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

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

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

principle of operation

There are many kinds of intake pressure sensors, such as varistor and capacitor. Because of the advantages of fast response time, high detection accuracy, small size and flexible installation, varistor is widely used in D-type injection system.

inner structure

The pressure sensor uses a pressure chip for pressure measurement, and the pressure chip integrates a Wheatstone bridge on a silicon diaphragm that can be deformed by pressure. The pressure chip is the core of the pressure sensor, and all the major manufacturers of pressure sensors have their own pressure chips, some of which are directly produced by the sensor manufacturers, some of which are special-purpose chips (ASC) produced by outsourcing, and the other is to directly buy general-purpose chips from professional chip manufacturers. Generally, the chips directly produced by sensor manufacturers or customized ASC chips are only used in their own products. These chips are highly integrated, and the pressure chip, amplifier circuit, signal processing chip, EMC protection circuit and ROM for calibrating the output curve of the sensor are all integrated into one chip. The whole sensor is a chip, and the chip is connected with the PIN pin of the connector through leads.