MAF sensor - air flow meter

Mass Air Flow ( MAF ) sensor

 

A car's internal combustion engine requires both air and fuel to work properly. The air-fuel ratio must be optimal to ensure uninterrupted combustion and improved engine performance.

In the past, a carburettor was the only device that controlled the combination of air and fuel. When modern engine control units (ECUs), also known as engine control modules, were invented, they changed the system significantly. Mass Air Flow (MAF) sensors are used to measure air flow.

 

What is a MAF sensor:

A mass airflow sensor is also known as an air meter . It plays a vital role in your vehicle. Namely, it measures the amount of air (mass air flow) entering the internal combustion engine.

Based on these real-time inputs, the engine control unit estimates the amount of fuel mass needed to keep air and fuel in balance.

In addition, note that air density changes with temperature, pressure, humidity, etc. Here again MAF sensors help. When it comes to measuring the amount of air admitted into each cylinder, they are more accurate than volumetric flow sensors.

 

Types of MAF sensors:

 

Paddle flow meters are an older type of airflow sensor. They are further classified into VAF, voltage, signal and Karman Vortex airflow sensors. The latter is newer in design. It uses a movable mirror and a phototransistor to measure airflow.

MAF hot wire airflow sensors are advanced MAF sensors and are more common. They consist of a thermistor, a platinum hot wire and an electronic control circuit. The thermistor is a temperature sensor that measures air temperature. An electronic control circuit keeps a platinum hot wire at a constant temperature. When air comes into contact with the heated wire, it cools. When the temperature difference between the two wires changes, the MAF sensor automatically increases or decreases the current to the hot wire.

There are also, cold wire airflow sensors that work similarly to their hot-wire counterparts. However, they have an additional cold resistance that allows them to measure ambient air.

 

Signs of a faulty MAF sensor:

 

Identifying MAF sensor performance problems can be challenging because they are not easy to detect. Here are some of the most common symptoms of a faulty MAF sensor:

A malfunctioning MAF sensor can lead to a variety of driving problems such as engine stalling, jerking or hesitation while accelerating. You may experience these problems while accelerating.

 

Why do problems occur?

 

Road debris, dust, dirt and other contaminants passing through the air filter can coat the MAF sensor wires and prevent it from accurately measuring airflow. Can send inaccurate airflow reports at lower speeds. As already explained, when the MAF sensor is not working properly, the engine cannot mix air and fuel in the proper ratio.

Cleaning the MAF sensor can therefore be a good starting point. However, to ensure the safety of your vehicle, consider having it checked by a mechanic.

 

Conclusions:

The mass airflow sensor is essential for the optimal operation of your vehicle's internal combustion engine. Based on the airflow measurement, the ECU balances the air and fuel.

 

In other words, without an MAF sensor, the car wouldn't work.

That's why you need to check and maintain it properly. Fortunately, MAF sensors are relatively cheap to replace.