Running rough
 

My cub cadet lt42 started running sort of rough last time i used it. Today it is running very rough. Will sound like it is running too "hard". Then will act like it is about to choke down. When it sounds like it is about to choke down, it will backfire and then rev back up. Some black smoke comes out of what it think is the muffler at the very front.

Please help!

What does the spark plug look like?

Likely running lean... something impeding fuel flow

Edit: Also forgot to mention that a condensor could be the issue sometimes... test it and make sure the connections are good.