Cummins 5.9 12 valve fuel PSI

[rseibenick]

Need to know the Cummins 5.9 12 valve fuel pressure PSI at idle and at 2000 RPM no load. Thanks.

[Skip426]

Are you after the pressure at the injector , or the lift pump supply pressure ?

[Scepter40]

17-22 at idle and 25-35 at 2500 rpm no load. That’s at the injection pump and is Cummins spec. And should never drop below 15 under a load for an extended period of time.

EDIT: I’m assuming you have a p-pump and not a VE engine. If so, let us know and I can find those numbers.

[1320Fastback]

VE pump 12 Valve is going to be a lot lower. 15PSI max or the injection pump shaft seal will blow out.

[Skip426]

For clarification , VE pump is the first picture , P-7100 commonly just called a P-pump is the second .

Please put the engine year in your post to help get you the correct answers .
These are the two common pumps for for the 5.9 12 valve Cummins.