The Check Engine Light may illuminate and/or a lack of power may be noted due to a failed high pressure fuel pump. BMW has released a service bulletin regarding this matter, the suggested repair is to replace the failed high pressure pump.
BMW 335i Problem Reports
Most Reported BMW 335i Problem Reports
A droning type noise may be noted when the air conditioning system is operating. Additionally, a vibration may be felt in the steering wheel. If these issues are no longer present when the AC system is turned off, the problem may be low refrigerant charge in the system. Our technicians remind us that if the refrigerant charge is found to be low, proper leak diagnoses should be performed in addition to recharging the AC system.
Noticed when having difficulty starting the car, took it to dealer, they said it was the fuel pump.
The Check Engine Light may illuminate associated with misfire codes stored in the DME (Powertrain control module). Most often no driveability symptoms are noted. Upgraded software for the DME is available which should correct this concern.