Hello, been a long time.

My 2002 Prairie 400 has started to run junky this season. Hard to start, sputtering, backfiring and just being a pain in my rear. I took off the carb, cleaned it out, blew out the jets, cleaned needle and seat, they were clean. Cleaned out the gas tank, it was clean, put in fresh fuel and it ran decent for a day, but now after sitting for a week its right back to it. Runs good with throttle and goes like a bat out of hell, but let off the throttle and it backfires and sputters and will not idle. Can hear it popping through carb sometimes at low idle speeds.
I remember it doing this same thing when it was new, and they said the "stator wire" had come loose. Anybody have a clue what I should check?

BTW, battery is 1 year old and fully charged.

Valves?