I have a strange problem. road a good part of the day, shut down for a couple of hours. when I went back out to ride, the ski wouldn't start. So I did basic system check. Battery ,wires, ect. Engine cranks but will not start. I pulled #3 spark plug to check for spark. As I cranked the engine it fired on the front two cylinders. Put #3 back in and the engine will not start. So I took #3 back out and the same thing. Engine fires on two cylinders. Short in #3 wire, coil? I did not try and remove the other two plugs and see if I get the same results.