I've got two of these evo .46's and they both have running problems. They don't seem to like the mix of cold weather and high altitude. I'm at 6000ft and it was 33F today. I rev them up and the run great for 30 sec. then the bog out. I've adjusted high and low end and had both our clubs instructors look at them and the can't figure them out. Please help!! I like these engines but I almost lost 2 planes today because of them.