1993 GMC C1500 smoking hard starting

The black smoke tells me it is running too rich (too much gas). Check fuel pump pressure to make sure the regulator is working properly. Also, there is a temp sensor that tells the computer the ambient temp and the coolant temp. Based on that, the computer determines how rich to make the fuel mixture for the engine to start. That could also be a cause. However, I would start with the fuel pressure.

Let me know what you find.
Joe