Your pics are a bit blurry but from your description it sounds like you modified the Idle speed control stepper motor. If you look in there a little closer you will see the throttle stop screw. Adjust that... don't use the stepper motor. It will run exactly where you want it to (700rpms, 800rpms, 900rpms... where ever you set it and like it) and if you adjust the primary throttle position potentiometer afterwards (to .6 volts) it will run like a charm. Just look at my "Fix" instructions...