My brand new engine, after running alright for a few days, is having trouble starting. I have finally gotten it to the point where it will start for about a second or two, and then sputter out. It feels to have no power during that brief second too. I have disconnected all the electrical stuff, and it does the same exact thing. I have checked almost everything, and really need to get this thing running? Is it possible it could be the cdi box? Any suggestions would be great! thanks