LSUh20fowler

Hi ya'll. Just joined a few days ago. Just bought my first yota last Thursday. I bought it to use for hunting and traveling back and forth to work. Its a '91 4x4 w/ the 22RE motor. It has 202000 miles on it. Bought it from original owner. Its beat up but mechanically in good shape. Theres a few things I'll fix up as I go. Not concerned with cosmetics, as it will spend the rest of its life in the woods. Heres my problem, from cold start, it idles fine. After warmed up, when stopped at light or sign, it will rev from 900 - 1400 RPM's w/o brake on. If I press the brake pedal, RPM's stay at 1300 - 1400. I did run seafoam through the brake booster line like I do with all my trucks and also run it in the fuel. Any help is greatly appreciated. I have 0 experience with Toyota.
Heres the ole girl


And heres my new truck I'm saving

LSUh20fowler

Come on guys, no ideas what the problem might be ?