The mass air flow sensor is also known as the MAF sensor or mass air flow metres. It is one of the key parts of an electrical fuel injection system and helps in estimating the right amount of fuel that needs to be used in the engine.
Modern engines need to know the amount of air entering the intake in real time. For this reason, the MAF sensor is extremely important. Read on and find more about mass air flow sensor, how it works and where it is located.
What Is a Mass Air Flow Sensor and How Does It Work
The mass air flow (MAF) sensor is an important element that the engine control unit depends on. When airflow enters the engine fuel injection system, the mass airflow sensor will analyse the amount of air flowing through it. It will then transmit this information to the engine control unit.
From there, the engine control unit will be able to control the amount of fuel injected into the engine. The MAF sensor makes sure the right amount of air and fuel is mixed in an engine’s internal combustion chamber.
Mass Air Flow Sensor Function
When the motor is idle, some air still flows around the wire. Therefore, it takes a very low current to heat the wires. When accelerating, there is an increase in the amount of air that slides over the hot film grid.
The greater the amount of air that flows through the fil grid, the greater the amount of electrical current needed to keep it warm. Hence, the electrical current needed to maintain the temperature of the film grid is proportional to the amount of airflow.
The information from the MAF is used by the ECU in order to calculate the amount of fuel to be injected. The purpose is to keep the air to fuel ratio at the optimum level.
Mass Air Flow Sensor Location
The MAF sensor is placed between the air filter and the throttle valve. Also, in some models, the sensor is inside the air filter box. If you have any difficulty, consult your vehicle manual, as it may vary depending on the make and model of your vehicle.
Symptoms of Faulty MAF Sensor
The bad mass air flow sensor will not be able to accurately measure the amount of air flow correctly, which is why the car computer won’t calculate the amount of fuel injected correctly.
As a result, we may face several problems such as:
- Difficulty in starting the engine
- Engine interruptions
- Dark smoke comes out of the vehicle’s exhaust system
- Low acceleration
- Increase in fuel consumption
- Rough idling
On the other hand, with a faulty MAF, the “Check Engine” light or warning lights on the car dashboard may also come on the instrument panel.
Over time, dust and oil particles accumulate and stick to the hot film grid. Incidentally, these particles may insulate the wire from the air stream, thus preventing correct readings by the MAF.
How to Test MAF Sensor
You can test the mass air flow sensor with the help of a scan tool. The reading of the amount of MAF is measured at different RPMs. The reading of the MAF sensor is usually measured when the vehicle is idle. The reading should be 1,000 RPM, 2,000 RPM and 3,000 RPM.
The contaminated air flow sensor shows low air flow reading, while a well maintained car MAF sensor will show a higher reading. However, it is important to note here that different engines may have varying readings. The readings usually depend on the engine size and are higher for high volume engines like V6 or V8.
Common Car MAF Sensor Fault Codes
Common fault codes and causes include:
- MAF circuit malfunction: P0100
- MAF circuit range/performance: P0101
- MAF circuit low input: P0102
- MAF circuit high input: P0103
- MAF circuit intermittent P0104
- The code occur due to a faulty or contaminated MAF sensor: P0171
Now you know the importance and functions of the car MAF sensor, hence it is important to keep the sensor fully functional and replace it if it shows any failure symptoms. In case your vehicle doesn’t have a MAF sensor and you want to upgrade it, then check out the listings of used cars for sale in the UAE. Here you can find a range of the latest vehicles at market competitive rates.
Stay tuned to the UAE’s leading car blog to get more information on the latest car technology.
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