Hmmm…2002 or 2004?
Anyway, if this 7-9 year old car never had its transmission fluid changed prior to the recent service at the dealership, it is very possible that the transmission is now failing.
Even though many/most mfr’s maintenance schedules no longer list trans fluid changes, the reality is that trans fluid needs to be changed every 3 yrs or 30k miles (whichever comes first). You did not tell us how many miles are on the odometer, but, based on elapsed time, this car should have had its trans fluid changed at least twice already (if it is a 2004 model), and it should have been changed at least 3 times already if it is a 2002 model. If there are more than…let’s say…110k miles on the odometer, then you would be ready for the 4th trans fluid change fairly soon.
However, doing a trans fluid change for the first time after 7-9 years is like locking the barn door after the horse has been stolen. Unfortunately, you can’t turn back the hands of the clock.
If the trans fluid has not been changed as described above, it is also possible that other vital maintenance has been skipped–hence the stalling problem. My suggestions are as follows:
Take the car to an independent trans shop for evaluation. Do NOT take it to AAMCO, Lee Myles, Cottman, Mr. Transmission, or any other chain unless you want to be told that you need a new transmission–whether you really do or not. If you do need a new/overhauled transmission, you may want to consider ditching the car if you don’t want to sink $2K-$3K into this 7 (or 9?) year old car.
If you are going to keep the car and have trans work done, then take it to an indy mechanic for all of the other skipped maintenance that is likely causing the stalling problem. If it is up to date on maintenance, it is possible that the engine merely needs to have the Idle Air Control cleaned or replaced.
There is no reason to take a 7 (or 9?) year old car to a dealership. Ask friends, co-workers, neighbors, and relatives for recommendations on indy mechanics and trans shops.
Good luck!