Hey guys. I'm back again. Had this little beast since August and I still have yet to drive it reliably. 2012 R56 Cooper S, N18 engine

We just replaced the HPFP with a brand new one from ECS tuning. Fuel rail pressure is still running at 74 (should be around 1100). Car keeps going in to limp mode of course.

We've replaced the fuel filter, fuel pump in the tank, high fuel pressure sensor and the vanos kit.

We replaced the HFPF first with a rebuild from a guy in Canada. It was working great for about two months. It gave me fits on my way to work this week. Pressure at 74. Came home and said screw it and bought a new one from ECS. Just installed it and I'm still showing 74 for the fuel rail pressure.

We are at a loss. What else could be causing the issue?

 

Have you measured the fuel pressure coming in from the pump in the tank? That should be 72.5 PSI. Insufficient fuel pressure from the low-pressure pump can cause delivery problems from the high pressure pump.

 

From Mitchell1