Hey guys we have a Scag 72" Turf Tiger with the 29 horse Kawasaki DFI engine on it. The thing is a monster as far as power goes, but whenever you start it or throttle up it surges in RPM's. Like you can put the throttle at any position and start the engine and it will start and after a second or so it will almost die, then its like it picks up fuel again and revs up. Sometimes it will onlt do it once, but other times it will do it a couple times. The same thing happens when you throttle up. It will rev up and then act like it is going to die, unless you go extremely slow while doing so. What could be causing this?