Bad Idle Air Control Valve?

Trying to work on idle, changed to open loop, locked timing at 20 degrees, then went into the warmup table and changed the % for the IAC, starting at 20 going up to 100 in increments, and there was hardly a change in idling RPM, like, virtually none.

Am I missing something?
 
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Try changing the setting to inverted. When I first started to get my car running the idle would run away. Changing to inverted fixed it. I'm no guru.
 
I'll give it a shot. I pulled the IAC off, setup my phone camera, and recorded the valve moving when I went to the test mode for the IAC in TS. It moves, but I still don't understand why the idle rpm stays the same.

 
I do not see the idle valve increase above 47% in the log file. Depending on the HZ used the valve may not be functioning until 45%, its minimum value would be 40% and Maximum at whatever value it stops raising the RPM. Remember at idle the valve has to overcome the vacuum pulling against it before it begins to open.
 
I do not see the idle valve increase above 47% in the log file. Depending on the HZ used the valve may not be functioning until 45%, its minimum value would be 40% and Maximum at whatever value it stops raising the RPM. Remember at idle the valve has to overcome the vacuum pulling against it before it begins to open.

how do I determine the correct Hz? I’m currently running 92Hz. And the fact that it doesn't seem to change the idling rpm as i sweep through the IAC values is kinda what got me on this road of diagnosing.
 
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Ok, ran from 45 - 100. fixed timing @ 20. I must have been doing something wrong before cause the rpm actually changed this time as I went through the different valve positions.

Also took the time to sweep timing. 10 - 26 degrees, IAC locked at 20. (If you can't tell I'm trying to follow your videos)

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OK, I finished following your idle setup videos. It is much smoother and stable now, and best of all I (for the most part) understand what I did and why.

If you can, take a look at this log and see what you think. The only notable thing for me was a slight hesitation on throttle blips, but it may just be perceived and not actually happening. AFR was a little rich for my taste on warmup so I backed off the adder on the WUE. Seems to idle around 13ish now, not certain where I need to be. I feel like when I cut fuel from the table it destabilizes the idle but that was prior to following your videos and I didn't test it very aggressively on this run.
 

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