General information
Hot-wire anemometric air flow sensor consists of a temperature-sensitive film sensor, housing and measuring channel (hybrid sensor element). The principle of measuring the mass air flow with this type of sensor is based on the fact that a change in the air flow flowing through the sensor causes a change in the amount of heat transferred from the surface of the element (films) film sensor to the air flow. The air mass sensor generates pulses, sequentially opening and closing the circuit, through which 5 V power is supplied from the electronic engine control unit.
The intake manifold air temperature sensor, located in the intake air hose, is a resistive type sensor that senses changes in air temperature. Based on the data on the temperature of the air in the intake manifold, the electronic engine control unit determines the required fuel supply.
- Intake Air Temperature Sensor: Resistance (at 20°C): 2.33-2.97 kOhm
Troubleshooting Guide
1. If the engine stalls occasionally, start the engine and try shaking the air flow sensor harness. If the engine stalls after this, check for a bad connection at the air flow sensor connector.
2. If the air flow sensor output is non-zero when the ignition is on (key position "ON") and the engine does not run, then the air flow sensor or the electronic engine control unit may be faulty.
3. If the engine is idling (even if the output voltage of the air flow sensor is not correct), then the cause is usually one of the following faults:
- A) Improper flow of air through the air flow sensor, disconnected air duct, or clogged air filter element.
- b) Incomplete combustion of the working mixture in the cylinder, malfunction of spark plugs, ignition coils, injectors and compression failure.
Air flow sensor output voltage:
- Rated value:
- Idle: 0.5V
- 2000 rpm: 1.0 V
4. Even if there are no signs of a malfunction of the air flow sensor, check that it is installed correctly (air flow direction).
Note:
- On a new car (mileage less than 500 km) The air flow sensor reading will be approximately 10% higher than the actual air flow.
- It is recommended to use an accurate digital voltmeter when carrying out checks.
- Before starting the test, it is necessary to warm up the engine so that the coolant temperature reaches 80-90°C.