car air flow sensor

Today, let’s talk about the basic principle and inspection method of the air flow sensor.
The air flow meter is installed between the air filter element and the throttle valve of the car to measure the amount of air entering the cylinder, and then convert the data signal of the intake port into the data signal of the working voltage and input it into the electrical control system module, and then measure the ignition of the electrical control system module. Advance angle, control the injector to inject into the throttle chamber (air inlet) of the car and the intake air supply is the best ratio (14.:7). At this stage, the air flow meters used in the car mainly include vane air flow meters, Lenny vortex air flow meters, vacuum pump rate (liquid level sensors) air flow meters (intake branch liquid level sensors), and hotline air flow meters. and heat pipe air flow meters. The vacuum pump rate air flow meter is an intake manifold level sensor only.
1: Vane air flow meter:
The vane air flow sensor is also known as a wing rotor or a suspended plate air flow sensor. The key consists of blades, sensors and terminal blocks.
Internal structure circuit schematic diagram
2. Central air flow meter.
The frame diagram of the sensor of the central air flow meter.
Type 1 and 2 sensor inspection methods.
1. The motor vehicle detection starter motor of the air flow sensor is located in the OFF position, and the wire connector of the core air flow sensor is unplugged. Use a digital multimeter resistor to measure the working voltage in the middle of the RF connector UC-E1 on the power line side should be 5V, otherwise the power line or ECU is abnormally modified or the power line or ECU is changed.
2. Air flow sensor parts inspection:
The starter motor is located in the OFF position, unplug the air flow sensor wire connector, remove the air filter device connected to the air flow sensor air inlet, remove the sensor fixing anchor bolt, and remove the air flow sensor from the car engine . First, check whether the measuring heart air flow sensor itself is cracked, whether the measuring heart is open, etc. Use a digital multimeter resistor to measure the resistance in the middle of the air flow sensor RF connector terminal to see if it is normal. If it is abnormal, the air flow sensor needs to be replaced. When measuring the resistor in the middle of the total air flow data signal terminal (US-E1), you must also move the measuring heart slowly to observe the change of the resistance value of the digital multimeter.