Mine does the same dang thing. Above 90 degrees it does the goofy idle and the bucking-bronco thing where it hesitates on a full throttle. I put 93 octane in it, and it seems to help. The stupid thing is designed to run at the very leanest it can be. Emissions laws! We have these dumb laws for those who ride and drive, but, if we go to sea, after 12 miles out, all tankers use a cheap, cheap diesel and you should see the bellowing cloud of pollution the comes out. What a joke the EPA is.