I have been experiencing a similar problem. Mine actually feels like the car is surging when coming to a stop and if it doesn't surge, it won't catch idle and it'll die. Mine doesn't do it all the time though. I'm going through my own checklist now to rule out anything mechanical.
2001 Firebird Formula A4 Uses the Stairmaster for 60 minutes a day...has never had to run to save his life.