Buddies XP 900 wont idle and dies

My buddy has a 2012 XP 900 4 seater that will not idle and eventually sputters and dies. We replaced the IAC and cleaned the ground cluster and no luck. If you unplug the IAC it runs fine but as soon as you plug it back in it starts cutting out. The new one is doing the same thing the old one did. It does cycle when you turn the machine off but sounds like it is struggling to do so. Anyone have any ideas before he burns this thing in the yard?