Low Rail Pressure, Tune or Truck?

[Wheelz]

Doing a mild tune for a friend, Its the only 6.7 I've done, however I've done a couple 5.9s and duramax's and don't recall seeing these results. Can someone take a look at the log and tune for me to make sure I'm not doing something stupid with Commanded Rail Pressure? Truck has 150k mi on it. We kind of suspect the lift pump is weak...

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[anarchydiesel]

more than likely the truck. FCA is maxing out on duty cycle, duration does not seem overly high. change fuel filter first, I have seen similar results with an overly dirty filter.

[Wheelz]

Thanks for looking at it. We had forgotten about a dirty filter. It's only a couple months old, but still could've gotten some bad fuel. Well post back what we find