I would check TPS calibration, when you unplug ISCV valve the valve closes as it has no power and therefore the only air that can enter is via the butterfly valve, the screw on the t/b holds the throttle plate open by a tiny amount just so a little air can get through for the engine to substain an idle, if it was allowed to close totally (I.E if the screw was removed) the engine would not run, the more you tighten the screw the faster the idle will get, the ISCV can raise the idle above base idle but not below.

Martin