Keep a lookout for electrical problems. Make sure the power steering gear and water pump have been replaced. BMW has identified a number of N63 engine components with high failure rates, including timing chains that stretch and snap, leaking crankcase ventilation and fuel lines, as well as malfunctioning fuel injectors, mass airflow sensors and vacuum pumps, fixed under warranty. May need oil top-up between services. EfficientDynamics fuel-saving systems cause short battery life, may require battery change on every service interval.
