What tranny? How many miles on the car? Turning left or right? Any CEL codes? Scan it at Autozone or Advance (even if the light is not on).
Suspect IAC valve, or massive vacuum leak (hissing sound, ticking). Stalls with foot off the accelerator.
For vacuum leak, use carb clean and spray near gaskets or connections. If the idle changes, you found the leak.
Read this thread.
http://www.contour.org/ubbthreads/showflat.php?Cat=&Board=trouble&Number=1274928&Forum=trouble&Words=iac%20valve&Match=Entire%20Phrase&Searchpage=0&Limit=25&Old=3months&Main=1274790&Search=true#Post1274928
