Originally Posted by 4cylinder4ever

I think it may be the Idle Air Control Valve. Because when your car comes to a stop the butterfly in the intake closes completely, so the only other way the engine will run is to let air bypass the through the IAC. If it's plugged up with gum and carbon, the air cannot bypass, resulting in the car stalling/hessiating/stalling when the foot is off the gas pedel / coming to a stop.

Try blasting it your intake with some carb cleaner:

warm up car to normal opperating temp. ( at idle run car until warm)

take the intake hose off of the intake

look inside beside the throttle body butterly, there should be a small peep hole

blast that hole with carb cleaner and while your at it blast the entire intake
too including the butterly. (it'll be messy so use a rag to catch whatever comes out)

when your done, start up the car again. you'll clouds of smoke for a few minutes. try running the car at idle for maybe 15-20 mins to get rid of all the carb cleaner.

hope this helps