hey I´ve had/having the same problems. What i did i took the carb off and just cleaned with carb cleaner. Once it was back on i started it and then messed with the idle a little bit. When i would give it some gas it was hold at 3 0r 4k, but then it dropped back down to about 1500k. i know it´s not ideal, but it wasn´t sticking up that high anymore.
but if you get some more specific info from anyone else on it let me know.
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