A Mass Airflow (MAF) sensor, also known as an “air meter,” measures the mass of air entering the engine air intake at any given time. When a MAF sensor is used in conjunction with an oxygen sensor, the engine’s air/fuel ratio can be controlled with great accuracy.
The MAF sensor provides the ECU with predicted airflow information (the measured airflow), and the oxygen sensor provides feedback in order to make minor corrections to the predicted air mass. This allows the correct amount of fuel to be delivered to the engine, ensuring optimal fuel economy and proper regulation of exhaust emissions.
When a MAF sensor fails and requires replacement, it may cause the “check engine” or “service engine soon” light in the vehicle instrument panel to illuminate, and drivers often notice sluggish performance, rough idling or stalling. There may also be a more frequent need to refuel.
- Unplug the connector pigtail from the probe, loosen the fasteners and remove the sensor from the housing. Then, inspect the flow tube for cracks in the plastic housing. If there are none, then it’s OK to replace only the sensor probe.
- Handle only the sensor connector. Touching the electronics may damage the sensor probe.
- Once installation is complete, connect a diagnostic kit, run the engine and check for any new fault codes. Exit the diagnostic software and switch off the ignition. Check that the malfunction indicator lamp has been extinguished, and then carry out a road test.
Courtesy of Delphi Product & Service Solutions.