My Car idles high, probably 2,000-2,500 rpms. The colder the weather, the higher the idle

I have had this problem for about a year and have been to several garages to no avail. I have let it idle for up to 30 m9inutes and still hitting the throttle doesn't bring the idle down. However, if i put it in gear and start to drive it will suddenly kick itself down to a low idle, sometimes in the first 200 feet but always less than a mile. I have replaced ALL SENSOR'S except the crank sensor and the knock sensor. I removed and cleaned the first throttle body, that didn't work so i bought a new one, no help either! I have removed the large vacuum hose on the master cylinder hoping it would rev up and that would be the problem but the idle is still high. I am confined to a wheelchair and it has been a real up hill battle trying to find the problem as it takes so long for me to find a way to reach things, lol. Today for the first time, it didn't kick down after driving it a mile? I drove 25 miles today one way and home and it was still idling high when i got home. seems like something went from bad to worse, lol. I should would appreciate any help anyone could give me.