ORIGINAL: Ih82crash
3w engines are famous for leaking air. Take the carb and the reed valve off and seal the gaskets with permatex. I had a similar problem with my 106 and after it was sealed it became very reliable. I do not believe that you have an ignition problem. My experience with ignitions is that they either work or they do not.
That makes a lot of sense. I will richen the high end first. If that does not work I will try sealing the carb.