X15 rough idle issues

[Valley11]

n the topic of X15. I have a 2018 X15 565hp. Demandated and running 605hp by Uni 2 years ago. Only 90,000km on truck the other day started to idle rough and smoke white haze. Rev up to around 800rpm smooths out and stops smoking. Once in awhile on start up runs smooth and doesn’t smoke never will safety twice in a row like this tho. Injector #1 was bad put new one in didn’t change. Sent all injectors away to get tested found all were gummed up do to lack of lubricant they said. They clean and set all injectors reinstalled them and acts the same. If I snap the throttle it will roll coal. While running truck no loss in power is noticed. Checked imap sensor exhaust back pressure sensor and tube all clean. Returned truck back to stock file started truck same rough idle and haze smoke rolls coal if snap throttle. Any thoughts what else to check?