My brother has an 03 Arctic Cat 400 4x4 and after driving through water just over the tires it is running terrible. If you gun it from a dead stop or once you hit about fifteen milles an hour it starts spitting and sputtering just like the reverse rev limiter does. I can't find any water in the air box, belt case or any where else, But I assume something must have gotten wet. He has driven through thatdeep of water before with no problems. Any ideas where to look or what it may be ?? TIA for any help.