Cm870 low turbo boost high EGT when freezing cold

[Chamberpains]

I've been helping a guy out that has a problem with his Turbo cutting back to low boost and then High exhaust gas temperatures while going down the road. He operates in a very cold region of the country. In my search to help him I ran across another Forum where they posed a similar question. The initial complaint is similar to what he's complaining of, then there's a bunch of gibberish from other people then the very last post from a guy named dynamo440 seems like a very interesting answer. I'm just wondering does that Ambient Air Temperature Sensor mess with the cm870's in cold weather.

Here's the link. Im only interested in the intial complaint and the very last guys response. Is there any validity to this threads answer?

http://www.thedieselgarage.com/forums/sh...p?t=114358