We have an 07 truck with a Diablo Sport programmer and sp diesel box on it with box turned off and just watching rail pressure at idle with programmer on any level from tow to rkl the rail pressure is up around 9k psi and shackes the truck like crazy kinda like its got a cam in it. We can turn the rail pressure down by using the sp box to -2 setting and bring it down around 7.5k psi and it settles down a little. We were told that they know that this is a problem and they are working on it but was just wondering if anyone else has seen this problem.

 

Nothing like you mention with my 03.

 

I have that same problem ............. I dont like it but sometimes I think it makes people think whats under the hood of that thing..........

 

Mine does it, but my rail pressure is only 7k or so. I'm not convinced the rough idle is a pressure problem.