Good grief... a 22 Fruitliner with an automatic, the world of heavy duty trucks and real truck drivers has certainly went downhill... I not so fondly remember driving one of the fleet spares for the company I retired from that had a DDEC engine it. Least it was a 13 speed. Having said that, it needed it because the torque rise on the engine was terrible as it could not pull any hill without serious downshifting.
All joking aside, whatever dealer you are dealing with, they seem to be somewhat incompetent or at least unwilling to contact DDEC to get advise on the issue. You can however call DDEC, they list their hotline number on their website if you look it up. They can assist you in determining the issue.
No idea where you are at but Freightliner of Toledo is a quality dealer and service center and can help you with your issue.
One of my very close friends and hunting buddy has 60 late model Freightliner Cascadia's and all of them get serviced and worked on there and he has little issues and what he has, they are attended to promptly.
I do know that early model DDEC engines has a big issue with hard carbon clogging the intake runner and causing engine issues as the sensors got fouled from the hard carbon that emanated from the EGR system.
I sure am glad my long nose Western Star has a mechanically injected 3406 Cat in it. I really don't care for a computer driven diesel, especially one with no torque rise and the overly complex emissions system that DDEC has on their engines.
