1994 Buick Lesabre high idle wnen warmed up to temp

Just take it out of its bore, with the engine off of course, and have someone turn the key slowly to the on position, it should move in/out. That indicated that it is working.

Do you have a check engine light on?

If this is the case, I would automatically suspect a vacuum leak.

If the engine light is not on, then a sticking throttle plate or linkage may be to blame, you will need a can of throttlebody cleaner and an old rag, and thoroughly clean the the throttle body, as far as you can go into it, of carbon. And do the same of the plate and linkage, you can hit the linkage with some wd40, and work it back and forth to loosen it up