While it is true that a hot spot can ignite fuel air mix and contribute to deiseling, if there were no fuel air mix it wouldn't matter. Long way of saying, get the idle speed down and the problem will be fixed. Even a normal engine can do this after a hard workout on a hot day IF the idle is too high. Run on was a big problem in the early days of smog equipment because of higher temps and high idle to run A/C without overload or overheat. The idle soleoics mentioned were and are the solution, if just dropping the idle to 550 or so doesn't do it.
