Won't idle. Engine cuts in and out.

What is your question?

My car will run, start up and sputter and die. One thing i know is my cat converter is bad and i was told it could be plugged, but the local mechanics here aren't the brightest here. As i was driving home from work the engine randomly started to cut in and out but didnt fully die but as it idled like i said it sputtered and died. If anyone could help any comments are greatly appreciated!