Thank you in advance for assistance!

Working on a 91 chev 350 with 1227747. Finally got it up and running with no error codes from SES and emulating from autoprom. Loaded the ADSU bin from here and tweaked a little for EGR, ESC, TCC etc.

A challenge I'm having is I can't get the thing to idle below 1000 rpm. We set the IAC a few times and the darn thing won't drop the rpm when it's hooked back up. We set it to right around 60. We took it for a quick test drive and upon returning the idle was at 2000 rpm w/IAC open at 145. It stuck there for 30 seconds or more then I could see the IAC counts dropping to about 18 and the idle drop to just under 1000. Then it raised the IAC to get the damn thing back to 1000.

I ave been playing with IAC - Desired C/L Idle speed and I don't get any change at idle. I have all RPM fields set to 600. Also, we installed a switch to the A/C input to the ECM for a high idle trigger, played with that too and didn't get any response.

Any ideas?