BMW E39 M5 MAF Sensors

Zoom-in view on Part Number

MAFs are packed securely

The MAF Sensor measures the flow rate of the air the enters the M5 (e39)'s plenum. The rate of flow that the MAF Sensor measured is then communicated to the ECU (DME), which in turn determines how much fuel needs to be injected into each of the 8 cylinders. A faulty MAF Sensor will cause your M5 (e39) to exhibit performance problems.

MAFS (Mass Air Flow Sensors) seem to begin to fail between 30,000 to 60,000 miles on the M5 (e39). The MAF Sensors fail because dirt and oily substances get baked onto them over time. Failing MAF Sensors will cause the M5 (e39) to exhibit intermittent problems such as a rough idle and power-loss. Some M5 (e39) owners have literally felt that their car became noticeably more powerful after installing new MAF Sensors. These owners probably had deteriorating MAFS for a while, and did not notice the slow reduction in performance, until the MAF Sensors failed completely, or were near the point of complete failure.

Sometimes the SES (Service Engine Soon or Check Engine Light) will light-up and a MAF Sensor error code will register (this can be checked with a code reader or by your technician). However, small amounts of impurities can collect on the MAF Sensors over time which can lead to drivability problems before the MAF Sensor is dirty enough to cause the SES light to come on. Replacing the worn MAF Sensors with new MAF Sensors can make your M5 (e39) drive like it should.

If one has to change their M5 (e39) MAF Sensors, one can simply visit their local BMW dealer and pay close to $1,000 for new MAF Sensors (housings and installation included). However, there is a much less expensive alternative, which is to purchase the kit that we are offering for sale here.

Remember that you will need 2 MAF Sensors. The BMW replacement part includes the MAF Sensor housing, which does not need to be replaced. All you need to replace is the sensor within the housing.

Some M5 (e39) owners have tried to clean their MAF Sensors, however, this has not been successful, with most seeing better performance for only a few days. Replacing the old MAF Sensors with new MAF Sensors is the only effective solution.