i had a simular problem a few years back. I was cleaning the throttle body after a good ol service (used carb cleaner) and used a tooth brush, anyway while the car was started i would spray it in and then turn car off and use a old tooth brush. Then start it bk up and rev it a few times while my mate sprayed it in there. Anyway what happened was that it back fired out of the throttle body and my face was in the way, lucky it was just a loud pop and i liturally ruined my boxers (lol) turned car of had a nose around and started it back up, when it fired up the revs wer all over the shop. Would rev at 2k then hunt like a c*nt! Phoned someone (creations motorsport in bham) he came out and reset the throttle body by using vag com (diagnostic laptop) and that sorted the problem. This may or may not help but plug in the ol vaj com and see what it shows up!
Hope that helps
sharki