LEMON Manuals: Even more car manuals for everyone
Home >> Ford >> 2009 >> Flex Limited, FWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 2044 (Engine Controls - Description & Operation (Hybrid)) >> Engine Control Components >> Mass Air Flow (MAF) Sensor

Mass Air Flow (MAF) Sensor

WARNING: This page is about a different car, the 2011 Mercury Milan, 2011 Lincoln MKZ, 2011 Ford Fusion, 2010 Mercury Milan, and 2010 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.

The MAF sensor uses a hot wire sensing element to measure the amount of air entering the engine. Airpassing over the hot wire causes it to cool. This hot wire is maintained at 200°C (392°F) above the ambient temperature as measured by a constant cold wire. If the hot wire electronic sensing element must be replaced, then the entire assembly must be replaced. Replacing only the element may change the air flow calibration.

The current required to maintain the temperature of the hot wire is proportional to the volume of air flow. The MAF sensor then outputs an analog voltage signal to the PCM proportional to the intake air mass. The PCM calculates the required fuel injector pulse width in order to provide the desired air/fuel ratio.

The MAF sensor is located between the air cleaner and the throttle body inside the air cleaner assembly.

Fig 1: Identifying Mass Air Flow/Intake Air Temperature (MAF/IAT) Sensor
G07432115Courtesy of FORD MOTOR CO.