black Smoke from Exhaust and Misfire.
 

I have a jeep Cherokee 2001 XJ 4.0 sport limited, and lately I've been having problem with misfire and a lot of lack of power.
the car struggles to move as it keeps stuttering.
i recently changed the fuel pump to Aeromotive and the throttle body to BBK as i was having this problem before.
But now again its coming back.
Now it even puffs black smoke from the exhaust when i'm on full throttle or even rev it a bit.
please help me with this problem.

obd2 codes?. sounds rich. o2 sensors. guessing.

Running rich could be the O2 sensors. Could be anything, really. Including the misfire. Running too rich for too long will eventually ruin the cat. So can misfires. When was its last tuneup? Check the fuel pressure, and for any vacuum leaks. And of course, codes.

Also, were the fuel pump and throttle body replaced before of after this started happening?