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Low rail pressure

1042 Views 2 Replies 3 Participants Last post by  Elsorrell1982
So im having low rail pressure when you first take off it will jump up to 12-13k psi but seems like it never wants to recover after that. Going down the interstate if you start pulling a long hill it will start loosing psi and get down to like 35 mph, 3k ish psi, and 30psi boost. If you drop a gear its same thing it just lays on its face.

New cp3, injectors, and fca.
I did check the fca by unplugging it and it changes nothing. You can even rev it up and rail pressure will go up some but not much. And it doesn't rattle if you shake it.

Last night I checked Pressure relief valve by taking the line off and it does have fuel coming up out of the sensor a little. I tried plugging it last night and still same runs like crap and no rail pressure.

Shoot me some ideas im pretty much clueless now!!!
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Rp sensor maybe? I'm not sure if it would even run on 3k psi. I know they won't start at that pressure. Just an idea for ya.

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I know this is old but did it ever get solved. I'm having same problem with mine!!!!
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