540 HFM/Mass Air Sensor, Bosch - E36 M3, E34 540i, E39 540, E32 740i, E38 740i, E31 840ci
Critical part for fuel, timing, and all-around engine performance. Stock replacement for M60/M62. Upgrade for OBD1 S50 and S52
This part is listed by BMW as BMW part number 13621702078 (13 62 1 702 078) and is described as the standard 3.5" HFM for 1993-1998 E34 540i, E39 540, E32 740i, E38 740i, E31 840ci. It's also a direct plug-in upgrade for E36 M3 with OBD1 wiring and proper software. The Euro and 540 HFM are identical except for minor differences in the housing where it would connect to a stock air box. If you're using this with a cone filter there is no difference at all. Bosch part #0280217800.
This larger HFM (MAF) is commonly used for tuning and increasing intake flow on US S50 and S52 engines, including engine swaps. It has a 3.5" diameter, as opposed to the stock US HFM (MAF) which has a 3.0" diameter. The larger HFM also has a greater resolution for reading airflow, which means fuel and timing corrections can be more precise.
Required: larger 3.5" air filter/intake, 3.5" throttle body boot, OBD1 wiring harness and ECU, appropriate software tune, and most applications require higher flow fuel injectors.
This is an OEM HFM manufactured by Bosch - the original supplier to BMW for this part, as well as many other components. As the OEM it meets all of BMW's original design, fitment, and performance requirements and is TUV approved. OEM parts are the best alternative to more expensive Original BMW parts because they are virtually identical without the inflated price tag. This part has a two year warranty.
For full BMW fitment information or for assistance from one of our BMW experts, we recommend calling us at 877-639-9648.
E36 (92-99) > M3 (1995)
E36 (92-99) > M3 (96-99)
E34 (89-95) > 540i
E39 (97-03) > 540i
E32 (88-94) > 740i
E32 (88-94) > 740iL
E38 (95-01) > 740i
E38 (95-01) > 740iL
E31 (91-97) > 840Ci