Just a thought but I think it is ULSD. My 03 did the same thing used to smoke lightly on acceleration, Now nothing. Still has its power though. but getting worse mileage since ULSD came to the pumps. I can go to the ranch fill up on the old fuel we have left and it will get better mpg and blow a light plume of black smoke when I get into it. But all the fun is gone when the tank runs dry.