[jsdowns]

I have an 04.5 with ppe dual cp3s and 100% injectors I have noticed when I just barely step on the throttle my rail pressure spikes until I let off. it stays around 24k pretty much all the time any ideas what it could be I have a new pressure relief valve it doesn't change if I take my smarty off maybe a bad sensor??

 

[Broaner]

Controller. Replace with another to check. Always the first place to start on a duals.

 

[cux211]

could be an fca acting up

 

[jsdowns]

Ok so when I take my smarty off I don't have any issues with the rail pressure but when I put the smarty on the rail pressure climbs really fast like it is more aggressive is this normal?

 

[Devilman]

What do you have the rail pressure set at on the smarty? If you've got it set to 4(I think that's what it is) then it's to high. When I was running a smarty R.P. was set at 2 if I remember right.

 

[Broaner]

What is the top pump? I'm running duramax FCA's and had to have some special tuning to make it not hang. Try to switch the top pump FCA to a cummins version if you are not planning on custom tuning to work around it. The dmax FCA's are a lot more touchy.

 

[jsdowns]

I have rail pressure set at default I am running ppe dual cp3s so it is a dmax pump.

 

[Broaner]

Change the dmax FCA to a cummins or the cummins to dmax. Make both FCA's the same.

 

[Chevokeeman]

My Dura-Max FCA failed at less than 1000 miles, full rail pressure at idle, installed a Cummins FCA on top Dura-Max pump to fix it. I suspect that the higher lift pump pressure required for the Cummins FCA, killed the Dura-Max FCA. 15-18 PSI on the Cummins and 12.5 PSI on the Dura-Max.

 

[Broaner]

I've been running 17psi on 2 dmax FCA's for a few weeks now. I was running 17psi on a single dmax FCA for over a year.