'92 Deville black smoke runs rough

Hey everyone, I have a 1992 Deville thats running rough unless you rev it and then you get clouds of black smoke. Smells really rich. Checked the codes and only got a 52 and 91. Oil and antifreeze check out ok so I dont think its a head gasket but I'm not sure what is making it run so poorly. It ran fine for years and this happened the next day. Anyone with any ideas please post!

Running to rich: high fuel pressure, low /no vacuum to map sensor, stuck injector, just some of many issues for an engine running rich, do a full on board diagnostic look at sensor inputs.

I'll start checking sensor voltages, think it could be a faulty pressure regulator or fuel pump?

Could be the reg., not the fuel pump