ive searched and searched on google and cannot find the answer. my truck is a 2007.5 deleted s&b intake, h&s xrt pro tuner and 4inch exhaust. no matter if its warm or cold out truck has rough idle and white smoke on start ups. then once it has reached operatong temp it clears up and randomly not every day it has a lil pop sometimes it doesnt do it at all. I had our shop diesel tech scan it and do injector kill test it passed everything what am i missing here?! any help would be appreciated.

 

See if you can get some ideas on this thread, kinda old though:

6.7 Rough Idle - Dodge Cummins Diesel Forum

 

i put some hot shots stiction eliminator in it and been running tcw3 2 stroke in it and its gotten way better so im hoping over time it will clear up whats in there and i know that the stiction eliminator is only good on fords but hell it works on my 6.7