ISX possible bad tune

[BlizzardGuy]

Hello all,
Glad to be here! (Post #1)

We have an ISX CM2250 that has been "de-mandated"
The company I work for has been dealing with a "tuner" out of country, and his tune seemed to be okay in the summer months

Now, when the ambient temps drop below -10 C or so, we get a ton of blue/grey smoke and a strong diesel smell, combined with rough running/hammering for the first 5 minutes at least of running. It smooths out when it begins to warm up and seems to run normal, until the next cold start.
I suspected a bad tune immediately, but of course he denies any fault and insists it must be something else
Thankfully the one who chose the tuner is also the one who owns the engine..
I should also mention that this engine received 6 new fuel injectors recently, fuel trim codes are correctly programmed

I haven't been inside a tune file for an HD engine yet, but am curious to know how to learn more about this
Does anything come to mind immediately for an experienced brain on this forum?

**EDIT**
I should also mention, that in suspecting this to be a tune issue, we had the ECM reflashed to stock programming.
The engine started and run like normal in the same ambient temperature as the de-mandated tune


Thanks in advance!

[Bengy88]

We can almost bet that’s a bad tune bud, especially if it runs normal after a factory reflash. I pm’d you instructions on how to pull it to have it checked.