Someone tell me the truth, do they ALL crap out, or what? 3 years full-time, ran pretty strong most of the time until early this year. Air filter and spark plug are new. Fuel is good. First it was hard to start, then it wouldn't stay running but finally once it warmed up, I could do a whole yard but it wasted 5 minutes to get it warm everytime. I'd have to let it idle because to give it throttle shut it off. Some folks said it was leaned out and to adjust the screws... There are none. I took it to the dealer, they slapped on a new choke and did some other stuff. Now it starts half-way decent, warms up so-so and I can give it throttle and eventually runs a half-way decent WOT but 4-5 minutes later it gets weird: At WOT, it starts to act like it's miss-firing and I can let off the throttle some but I just can't get nothing out of it. This can last as long as it lasts, then suddenly it revvs up again and runs great for however long, usually just long enough to get me excited then it does the miss-firing bit again. I don't know if it's miss-firing, it just sounds like it and there is a rotten smell coming out of the exhaust when it does that (unburned 2-cycle fuel is what it is). I removed some rust from the muffler, there is a nice hole there now but the screen is still in place but yes, it can breathe. I mean, should I order a carb ? Or is it the engine?