FIXED I know that there is a whole thread dedicated to this matter but I've tried pretty much everything on that list, it's possible I missed something need some help.

The other day I decided to look around for anything obvious such as vacumm leaks. I put something with a flat metal surface to cover the throttle body and after I did this my car started idling at around 400rpm.
This definitely means air is getting through but I cant seem to find where. I'm hearing compressed air around the throttle body but I cant feel any air leaks in the surrounding area.
It kinda sounds like its coming from the Fast Idle Thermo Valve (I already replaced this), and also when I cover the small hole inside the throttle body my idle surge stops and starts to idle healthy (750)
Can I assume the FITV is the culprit? I think its stuck open but I could be wrong, if anyone has ever experiend this problem please help.
I'm going to open the FITV and try to adjust it today after work.

 

Idle surges when in NEUTRAL and when in GEAR, maybe its not the FITV?

 

FIXED This problem was bugging me for months, it turned out the be the FITV.

I had actually replaced that valve with a brand new one and had no luck, probably why it took me so long to fix was because I wasn't looking in the right direction.
The valve was filled with sludge and seemed to be stuck open.

Instead of replacing the FITV I spent roughly 24$ on a Route66Mods FITV Block Off Plate.

 

If you live where it gets really cold in winter, you might miss the FITV. It's job is to make cold starting easier by letting the intake have more air at first. As the FITV clamps down, the idle slows, and the IACV takes over. The temperature of the coolant passing through the IACV tells it when it's time to go into action.