Originally Posted by 65mechanic
does this howling sound increase in noise when you rev the motor? I have a similar noise when the car is cold.
In my experience the IAC related "howling", "honking", "French horn" noise has been unrelated to engine speed, and discontinuous--often silenced by "blipping" the throttle.
I would suggest that you may have another issue, perhaps related to some engine driven auxiliary device. Failed/failing generator, power steering, water pump, or idle pulley bearings can create engine speed related whines/howls/etc...