Yes. Kinda.... to be more precise, it means: "All the fuel didn't burn"Isn’t black smoke (rolling coal) a symptom of lots of fuel?
That can be because there is "too much fuel"....
But it can also be:
1. Poor burn / incomplete burn (there are many causes for this condition)
2. Insufficient air (ie plugged air filter - but that is apparently not the case here though)