High idle 2200rpm

Any ideas chaps, my gta turbo has started to idle at 2000+ rpm, it has happened occasionally before in the past but always settled down after a minute or two. It use to happen when warm but now it seems its all the time from cold . Could this be a throttle body or sensor problem. Any help or ideas will be greatfully received . thanks

Try cleaning the idle/bypass valve.LHS of engine,has pipes from inlet plenum to throttle body.
These gunk up with oil and can stick.Take it off clean,brake cleaner spray can.If you twist it sharply,like a bike throttle, you should hear it move.

Also worth checking that the throttle cable linkage is moving freely - had a similar issue years ago and some lubrication of the cable etc.