Originally Posted by Oulixes
Siemens made the pumps in the early days of the N54 engine. Subsequently, Siemens sold their VDO division to Continental and BMW used in the N54 pumps made by Bosch; currently, BMW uses the pump made by Continental. All three companies involved in manufacturing the pump know as much about making fuel pumps as BMW knows about making cars. The cars that fail due to fuel delivery usually experience problems with the pump, fuel injectors, etc., which seems to indicate that the problem is not limited to the pump, but rather it is due to the integration of the fuel delivery system. It appears that the components of the fuel system incur cumulative damage that in many cases culminates in the failure of the high pressure pump. There is no doubt that the N54 is an engine deserving praise for the originality of design and the performance it delivers. Reliability is different matter - it is more difficult to evaluate and less glamorous to write about.
...Yes, for the most part, Thank you!!
No the pump isn't the only issue, there are others, but its usually the first to go. Fuel quality makes a big difference. The Bosche HDP in the Diesel has no issues..... But that's a totally different animal (environment), with diesel!