Every air flow meter is made based on the thermal sensing principle. Today’s advanced air flow meters feature rugged industrial packaging and are available in the variety of insertion and inline configurations, making them the ideal instrument for a wide range of precision both industrial and commercial air and gas flow applications. For your replacement needs, you can count on Replacement air flow meter which can easily be found online. So to speak, your air flow meter is nothing more than a fancy variable resistor.

Inside it is a flap that deflects in relation to how much the air is entering the engine. Attached to a wiper arm, this flap wipes across a restrictive track. A fixed voltage is sent to the air flow meter by the ECU. Now, the electrical resistance of the air flow meter increases as the flap opens, giving the ECU a measurement of how much air is entering the engine.

The air flow meter is tested electrically by attaching the leads of an ohmmeter to the proper terminals and measuring, the resistance offered by the air flow meter as the flap is moved through its travel. The data supplied by the air flow will be used by the ECU to help determine how much fuel to inject. Contained in an air flow meter is a temperature sensor for the intake air. This sensor is a semiconductor that varies resistance with temperature in an inverse relationship – the higher the temperature, the lower the resistance. This useful information is an aid to determine how much fuel to inject as intake air volume, supplied by the flap, and intake air temperature, supplied by the sensor, can be used to calculate intake air mass, on which the computer calculates the correct amount of fuel for that given mass of air. The other parts of air flow meter include temperature sensor and a fuel pump switch.