Everything you need to know about the air flow sensor

By regulating the fuel injection, the air flow sensor helps reduce fuel consumption and optimize the engine service life. Thus, this essential mechanical part ensures the proper functioning of the vehicle. Provided you maintain it well. A defective or poorly maintained air flow sensor can quickly increase your gas budget! In this article, Klaxcar shares everything you need to know about the air flow sensor.


A brief overview of the air flow sensor

The role of the air flow sensor is to manage the air volume injected into the engine. This sensor adapts its operation according to the air mass present in the vehicle system. The air flow sensor  continuously measures the airflow circulating in the engine. It then transmits this data to the  calculator. The latter then determines the fuel to be injected to maximize efficiency, thus optimizing the air/gasoline mix within the engine. Overall, the calculator plays a central role in the modern engine operation. It also deals with components such as solenoid valves, actuators, the ignition coil or injectors.

As a motor accessory, the air flow sensor is placed at the air filter outlet. This auto part consists of a plastic tube containing a sensor and a probe for air temperature. The intake air circulates inside this tube. The sensor is a hot film including a heating resistance kept permanently at the same temperature thanks to the electronics specific to the flow sensor. When the airflow increases, the  resistance  cools down. The air flow sensor must increase the current intensity, which ensures a constant temperature. As for the air temperature probe, it contains an  NTC-type (Negative Temperature Coefficient) resistor. When the temperature drops, the resistance increases.

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These signs of malfunction of the air flow sensor that you should know

It is important to respect the replacement interval of the air flow sensor. There is no standard service life for this car part, but it usually needs to be replaced after 93,000 miles. Take the opportunity to change your air filter as well to protect your new flow sensor. Some signs can help you spot the aging and malfunction of your mechanical part. Pay attention to the following signs:  

  • The engine control light on the dashboard remains lit;
  • Your vehicle loses speed and power;
  • Your level of fuel consumption is abnormally high;
  • Your car often stalls;
  • Your exhaust pipe gives off black smoke;
  • You can no longer start your vehicle.

Repeated stalls, overconsumption, loss of power, slow motion, indicator on... these are all signs informing you about the urgency to replace your air flow sensor. Generally, they are the consequence of mechanical fouling that gradually deteriorates the car part power. Remember that the air flow sensor is a very fragile component. It is difficult to handle and should be replaced as soon as the first signs of malfunction appear. Cleaning the part is as delicate as it is unnecessary as the system has a self-cleaning device for the hot film. It is not recommended to touch the air flow sensor yourself, as some elements can break easily. If you really want to clean your air flow sensor, start by disassembling it. Then soak the lower part in degreaser. Leave on for about ten minutes. Then use a thin brush to carefully rub the filaments in the tube. Cleaning does not exempt you from changing the part when it does not work anymore. A dirty air flow sensor should be replaced by a new part.


In case of neglect of the failure signs, the air flow sensor will stop working normally. By default, the calculator will determine a constant flow value and your car will lose power. To be sure of the air flow sensor failure, you can have electrical measurements made.


Air flow sensor: Klaxcar brands and references

There are many air flow sensor brands on the market like Mapco, Facet and Bosch. Klaxcar references offer you the best value for money. You will find all our air flow sensor models on our webcatalogue within the range of sensors and valves. Our expert team has gathered various references for you. Find reliable and efficient auto parts, enjoy Klaxcar quality as a bonus!  


Today, car models give prominence to on-board electronics with increasingly complex components, including the air flow sensor. With Klaxcar by your side, you also have competent customer service and advice tailored to your needs!