As BMWs get more sophisticated, it's only natural that the technology used in their water pumps advance too. The majority of BMWs are being released from the factory come with electric water pumps that are designed to work when the motor is off (for vehicles with the automatic start/stop feature), as well as reducing engine load so as to improve performance and economy. They have the tough job of moving a huge volume of coolant through the engine at very high pressures, so it's understandable that these units can fail at times. This electric water pump (manufactured by Pierburg in Germany) is the exact same that is sold at the dealerships.
OEM Part Number: 11518635089
OEM Part Number: 11517604027
OEM Part Number: 11518625097
Pierburg Part Number: 7.03665.66.0