I would guess the fuel pressure regulator is at fault...but I don't want you to continue to throw parts at the problem...

...do the diagnosis one step at a time...fuel pumps on, fuel relay operational, fuel injectors and seals okay, etc. etc.

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2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car