idle is radical on 2001 Hyundai Tiburon

engine idles high then low high then low up and down then when I pull up to a stop in about 30 seconds it will go to normal idle.

3 answers
idle control motor is bad. it is easy to fix but expensive. mine went bad about two years ago and im finally getting around to replacing it
Have you checked for any diagnostic trouble codes? Check for vacuum leaks as well.
My car (2004 Tiburon GT) is doing the same at the moment, Mechanic still hasn't solved the problem... Did you work out what was wrong in the end????

Jack