[scarceller]

If it's running but running rich it could be a faulty CHT sensor.
These sensors are inverse temp to ohm spec.
Initially at cold start the sensor should read 1800-3000 ohms depending on cold temp. Point is they read high resistance in this range on a dead cold engine.
Once the engine is fully warm the sensor MUST read less than 200ohms.
I'd start be testing the CHT resistance on engine dead cold, report this number back here and the ambient air temp.

Another little trick, once these engines are warm you can unplug the CHT sensor and jumper the 2 female pins in the harness with a piece of wire. What this does is set the resistance at 0 ohms and this tricks the DME into thinking the engine is fully warm. You can actually run the car once warm like this.

Black smoke at the tail pipe is way super rich! Start by determining if the CHT sensor is good or faulty.