Air Flow Meter/Sensor: Description and Operation

PURPOSE/OPERATION
The mass air flow sensor is a hot film type sensor. The film is located in a housing along with the metering duct.
Air flow rate is measured by reading the rate of heat transfer from a hot film probe. The change of the mass air flow rate causes a change in the amount of heat transferred from the hot film to the probe surface.
This results in a varying resistance that is sent to the engine control module.