very expensive if you bring it to a shop.
wouldnt suggest doing unless you were mechanically inclined, about 250-300 bucks in parts.
I have the same problem..Everytime that it begins to happen, just turn the car off and wait 5-10 seconds and then start it back up. It will be fine again to go!
Jason
00 Audi S4, 2.7 Bi-turbo quattro

01 S10 Xtreme, 4.3l
98' Contour SE with some mods
96 Cavalier (beater)