Please help..smoke, clicking sound - fuel pump???

I have a 1996 Chrysler Concord 3.5 engine, it wouldnt start last night, but started this morning, it happened again today, when I finally got it started a huge billow of dark smoke came from the tail pipe. While driving, it felt like it was going to shut off, more smoke came out, there is also a clicking sound (dont know where its coming from) and when I am going up a hill it starts jerking and going really slowly. I have no idea what this is, one person said fuel pump another said can't be the fule pump, since it does start and I can drive it.

Any help would be appreciated.

Thanks