WOT how to idle?!?!?!? Sorry, no offense, but i dun get what u are trying to ask now....

WOT = WIDE OPEN THROTTLE, which mean engine is running at MAX RPM.....idle = engine is running at the lowest RPM to sustain b4 dying....so which is exactly your problem?

Low end cutoff/engine choke or high end choking?

Your fuel may also cause problems to the running if the nitro content is already weak...never keep fuel for more than 3-5mths...