Hyundai Forum - Hyundai Enthusiast Forums - 2009 Hyundai Accent transmission

Hello every one,
I have a 2009 Hyundai Accent also and i live in a area that has speed bumps. Every time i take off after the car has sat for a while the transmission will jerk hard. I took it to the dealer who test drove it and said i don't feel anything. I told the teck to slide over and i will drive it and show him what it is doing. Like most tecks when they get in a car they push the gas hard and take off. I told him this happens between 10-20 miles hr. It jerked did happen again and the teck said i don't feel a thing. He took the car back into the stall and brought it back out 15 min later and said i erased the transmission memory and it will have to get used to how you drive the car before it will stop. I looked at him like he was a IDIOT. The car is still jerking at the lower speeds. I have 42,000 miles and had to buy another warranty from a diff dealer because Hyundai said if i did not buy it from them they will not sell me a additional warranty, even though it is still under the orginal warranty. Anyone have a idea whats happening?