Ok, since it is now WELL below zero in my part of the country, my IAC howls for about 5-7 sec, when I first start it up, and then goes away for the rest of the day.

Should I look into swapping it out, or let it howl for 5 seconds and keep on trucking? Performance is still smooth as ever. this has only started since it has dropped below zero. If I keep it garaged, it does not do this. Thanks!

It's probably on it's way out, but if it doesn't do it after startup or in warmer weather I'd wait to change it out. I'd go ahead and buy a new one and throw it on the shelf.

Thanks Alec, that is what I will do.

A temporary solution that sometimes works is to pull the black cap off of the IAC.

You could try cleaning the little felt filter. It is under the black plastic cap on the side of the IAC. There is a plastic piece that mounts to the IAC and a cap that fits over that. Just remove the cap and pry out the felt pellet and clean it. In some cases this has cured the problem. This vent takes in air to balance pressure on the valve and keep it clean.