Gasoline - Hyundai - Elantra - Shifters :: 2008 - Car Wants To Stall When Accelerating

I have a 2008 Hyndai Elantra with an automatic transmission. Since the first week I have had my car when the fuel is low (under a half of tank) the car tends to hesitate like it wants to stall, or momentarily shifts into a higher gear than it needs to be for the situation; the rmp's get very low. As the tank drops further below half full, the problem gets progressively worse, especially while trying to accelerate hard; i.e. entering the highway, starting from a red light, etc (times requiring a lower gear). I have brought my car to the dealer for service three times also asking them about this problem. Each time they can not replicate the problem which seems ridiculous since it is difficult to not have the problem when the tank is low.

The day I purchased my car I was speaking with another Elantra customer who was waiting for her car in the service department. She had just purchased her vehicle as well and already had to bring it in for a fuel pump recall. I believe the recall states that the fuel pump fails and causes the car to stall, sounds very similar to what my car wants to do. I have asked about this recall on my vehicle and have been told that it does not affect my car.