The function of automobile air flow meter is to monitor the amount of engine air intake, and convert the air intake information into electrical signal and transmit it to the electronic control unit (ECU). The ECU determines the fuel injection quantity of the engine through this signal. The symptoms of automobile air flow meter failure or damage include unstable idle speed, poor acceleration, increased fuel consumption, weak high speed, black smoke from exhaust pipe, excessive exhaust emission, etc.
The abnormal air flow sensor will not cause the engine to start, but it will affect the dynamic performance of the engine. Air flow meter damage is often due to the air filter is not replaced for a long time or the use of poor quality air filter, resulting in the air flow meter hot wire dust accumulation time is too long, resulting in inaccurate change of resistance value or failure, dust will also lead to the throttle valve is too dirty.
In order to obtain the best concentration of mixture under various operating conditions, the air flow meter must correctly measure the air intake into the engine at each moment, which is the main basis for ECU to calculate and control the fuel injection quantity of the engine. If the sensor or circuit fails, the ECU will not get the correct air intake signal, and it will not be able to control the fuel injection quantity normally. The mixture will be too rich or too thin, and the engine will not run normally.