2002 Hyundai, Sonata LX V6 engine idling high to fast

I agree with rasmataz on the Idle air controller and the vacum leaks. You may want to take the IAC off and clean it with carb cleaner. I would also check to see if your PCV is working and make sure the MAF sensor is clean.
Don't use oil impregnated air filters on these cars, they seem to interfere with your MAF sensor.

You could also use a can of Intake Cleaner and clean the intake with it. I noticed a big difference in how well the engine ran after I used this. (Make sure you use INTAKE cleaner, not Carb cleaner!) It probably won't be the fix for your specific problem, but it certainly helps your engine run better.