not necessarily, not even if there is no other problem. the iscv is only there to raise the idle above a base speed when the engine is cold or has a load on it (plling away without throttle) or high electrical load.

when warmed up a little, and hopefully even when cold it should still idle without the iscv connected, albeit possibly at a low speed. if it doesn't, the throttle plate is closing too far or the air bypass is too small and the base idle needs setting up.