HFM/Mass Air Sensor, BMW - E46, E39, Z3, M52TU, M54

This part is listed by BMW as BMW part number 13621432356 (13 62 1 432 356) and is described as HFM (Hot Film Meter or Mass Airflow Sensor) the for M52TU and M54 engines used in E46, E39, and Z3 models.

The HFM (Hot Film Meter, or MAF sensor) measures air density and temperature so the engine computer can make fuel adjustments on the fly. There are several possible failures with an HFM and not all will trigger a fault code. Poor sensor data can make the car run rough, surging idle, poor drivability, and decreased MPG. First try cleaning the HFM and inspect all of the intake boots for cracks or loose fitment. If problems persist it may be time for a new HFM.

In our view, a Genuine BMW HFM has stricter tolerances and better performance than any other brand of HFM. If performance and expectations are your most-valued considerations, our recommendation is a Genuine BMW airflow sensor. It's worth the higher price for the better and more consistent performance. If price is a major factor, look to the OEM and aftermarket brands.

This is a Genuine BMW M54 HFM with a two year warranty. Buying a Genuine part will usually be more expensive than an OEM or aftermarket brand but you are assured that it meets BMW's designs for fitment, performance, and longevity. It will also be the very latest design, incorporating any updates or revisions that an aftermarket brand typically will ignore.

For questions or for assistance from one of our BMW experts, we recommend calling us at 877-639-9648.