Black smoke from Exhaust on 2015 Freight Cascadia

[mazhar586]

Hey Guys, need a serious advise.

Im the owner of a small company having 2 trucks in fleet. In January this year I bypassed the DEF on my Freightliner Cascadia DD15. Once the job was done, the day driver took the truck out while driving he noticed White smoke coming out from the exhaust (the exhaust is located at the bottom of the truck) white Idling & pushing gas, the driver noticed that it wouldnt always do, which means the smoke would come every now & then. Luckily I was still at the workshop getting done with payment & paperwork, I told the mechanic & he asked the driver to come back so they can have a look at it. The mechanic was like there might be a possibility that the DEF pump was not disconnected in the entire bypass process. Well, he disconnected it & said that you would still see the white smoke until the DEF is all gone from the tank.

Later that week, the day the DEF bar was blinking red (DEF tank being empty) the truck started throwing BLACK smoke instead of the white smoke. Now this was even more scarier, so i called the Mechanic & he was not to sure why was it doing that. He was like it could be the Injectors, engine or anything so he asked me to bring the truck back in. I have already spent $3000 n the bypass & GOD knows how much more would i have to spend. Prior the bypass we didn't have any problem. Im assuming would it be the programming that must have been wrong after doing the bypass? Please help me, things like these are scarry.