I read this from another diesel forum : life is simple, black smoke = too much fuel or too little air. check air filter? what kind of boost does it run? possible turbo/wastegate issues? charge air cooler leakage? maybe a reflash of ecm or boost sensor reading incorrectly?

Wouldn't these issues set off any codes ???

99% of all the black smoke pictures, movies, and stories on this site come from chips that add more fuel than the motor needs, combined with other chips and lift pumps. so when the exhaust exits the tailpipe it leaves as a cloud of black smoke.

When those other issues occur they may or may not throw a code depending on how bad they are