Engine revs up to about 1600rpms at startup because the IAC Parks at 160 counts. After startup, it takes about 15-20 seconds to lower to about 20-30 counts to maintain a perfect 750 idle.
Don't like engine revving that high with no oil up to the moving parts at startup. I don't live in a cold area, its rarely below 32 degrees, so no cold startup problems, and besides I can control the target idle for that.
Any reason I should not make the IAC Park at 50 or so in the PCM program?

 

is yout TPS voltage between .5 % and .9 % ?
if not correct that first.

Otherwise yes you can adjust your IAC tables. If it only does this at cold startup temps you can turn these down so it doesnt open up so much at cold start up. You can also turn your IAC position vs vehicle speed down if necessary. I ahd to do just that to mine as I had the same problem

 

TPS volts are at .63 at idle.
I reprogrammed the IAC park positions to 40 at all temps above 0 degrees C.
But still when I turn the key on, the IAC COUNTS are at 160 and revs high at start up???

 

How old is the IAC valve itself?
And if new, where did you get it?

 

Its a brand new Delco IAC. The old one was stuck about half open because the motor set up a long time before it was transplanted to my truck.

 

Someone told me once before that the values in the IAC park position table are just a "reference" that the PCM uses. It's still going to adjust to whatever it needs in order to have enough air at idle.
So I'm not exactly sure what that table really does.

 

That's correct, the IAC will step in or out how ever far is needed to obtain the programmed idle speed, and that part of it is working just fine.
The issue is that it is parking all the way extended at 160 counts/steps, so at engine startup, there way too much air entering the TB and it revs to 1600-1700 rpms for the first few seconds until the IAC closes down to about 30-40 steps.
What I want to make it do is Park at engine shutoff somewhere in the neighborhood of 40-50 steps.
As of right now, I can't tell the the "IAC Park / Temp" table is even doing anything.

 

That high idle when you first start is what my Mustang does (I hate it). I wish it were as easy to modify as LT1's with a program like Tunercat.

 

I would just set it up to where you have between 30-50 steps in gear at idle. As long as it's above 0 counts in park you're fine.
Have you tried this?

 

I always thought the table was a + modifier for the value the engine is really running at.

Ie if the pcm is using a value of 50 steps this table will + that step with whatever is defined.

I think i proved this to myself once before.. dunno tho