I have been chasing down a poor idle condition for about 6 months now. I FINALLY found it!!! Whoo-hoo. I started doing the worst thing you can do, replacing so many things at once to try and fix the problem, I created many new problems. It all started with a bad TPS. I replaced mine, but messed with the stop screws on the throttle body essentially closing the butterfly valve. So, needless to say, my truck still ran like crap. I couldn't figure out how to get everything back to normal settings.
So...
I bought a used TB off ebay (40$, like new) and just stuck it on yesterday. I started the truck up, and to my amazement, IT RAN GREAT!!! Wow, all the power back (all it ever had anyway) NO chugging or coughing or sputtering while slowing down.
However, when I came to my first complete stop, the idle went WAY high, no tach to tell exactly how high. It was quite high though.
I started off after the stop, and the truck continued to run great while driving, and at the next stop the idle went high again. It was like the truck didn't want to go out of high idle. So, I stopped again, and turned the idle screw down some, which did lower the idle, but it also made it chug a little when starting from a dead stop (nowhere near as bad as with the TB butterfly closed, but noticable.)

Now after all this long-winded background story, here is my question:
What can make your idle go high (kind of "stuck" in high idle/cold start mode) ? I ask this because all the power is back from the TB swap, but I'm thinking there is something else wrong with it to keep the idle high, rather than just turning the idle screw almost all the way down to keep the idle down. I think that is just masking the real problem. Some of my poor running to begin with seems to be due to my turning the idle screw almost all the way down on the old TB.

Thnaks for any and all information/help!
Jason