Fuel is needed to run a car. This requires air (oxygen) in addition to the fuel (for example petrol). An air mass meter is used to obtain the perfect composition. This meter is linked to the air filter. This allows the amount of air entering the filter to be registered. In addition, the density of the air is also measured. Finally, these data are passed on to the software, after which the amount of fuel is adjusted. The air mass meter contains a wire which is heated by a constant current. The air that enters flows along this wire, causing the temperature to change. The resistance will change due to this temperature change. For example, if the resistance drops, more current will flow through the wire. This signal is then passed on.
Dirt or wear can cause the meter to work less well or break down. This will cause the meter to take incorrect readings and give incorrect results and thus create an incorrect ratio of air and fuel. For example, the car can lose power. An air mass meter can easily be cleaned with a brush and after cleaning, sprayed with contact spray. If it is really broken, the meter may need to be replaced.