Strange idle when cold

[zig80toy]

I completely love this truck but now have one complaint.
Background: 2005 dodge 2500 cummins diesel. 36,000 miles, completely stock.

Problem: When i fire the thing up in the morning and let it idle while i'm out scraping the window it idles just fine for about 2 minutes. After that its starts to surge. The idle bounces between 800 and 1200 until i give it some throttle. and it doesn't take much, i just barely tap the gas and the surging goes away. Then its fine for about another minute and the surging comes back. tap the throttle, goes away, etc...

 

[Lucky Jeff]

You'll have to double check, it's been a while since I've talked to anyone about it. But they had a problem with the crank sensor and cam sensor not playing nice.. Can't remember what kind of fix there was for it. Usually it caused the truck to not want to start on the first or second revolution after it had been run for a while. Maybe that could also cause what you're having troubles with. Not totally sure though.