sounds like idle surge. i too am in your boat. I already figured my problem out tho, i gotta bad ISC motor. there's a few things it could be. check out the link below, it has a good lil step by step method of figuring out what it might be. I found mine to be a bad coil in my ISC motor. my ohm readings were 35,35,35,62 , and all my buddies had 29 across the board. But anywho, check out this site for some help
http://www.myzero.com/engine/surge.html