Gear
Parts on Order
This is probably a turbo that blew and the engine is running off its own oil. Turbo blows, oil goes into the engine, engine runs off oil, no idle control, high idle. Putting something over the intake would shut it down. Examples phone book or a piece of wood, something strong. Or you could just let it blow, probably needed a new engine anyways.
Disconnecting the batteries like the guy suggested would do nothing. The engine is running off its own oil, so its completely mechanical.