I have had this problem for awhile now and I want to get it fixed. When ever I punch the throttle and then come to a stop it has a high idle, about 1200ish. I can get it a little lower by bliping the throttle but it usually just takes time to return to normal idle, 600. SOOO I believe it is a throttle linkage, butterfly problem. The linkage feels like it is all the way back down (idle) as in it isnt getting hung up or anything like that. Maybe a stiffer return spring might help?