When driving regular speed, the car jerks/kicks back only once.

Hello, This is what we call an intermittent problem, and diagnostics will be necessary to figure out what is causing the issue. Professional diagnostic equipment will be used to view data generated by sensors, and a technician will have to rely on their training and experience to diagnose the issue. Now, there is something I recommend you try if you have a multimeter, and a little understanding of the throttle position sensor. If so, let me know, if not, you will want to select a German or European specialist. Even if the location specializes in BMW or VW, Mercedes will likely be serviced there as well. Here is a list of certified shops in your area: http://repairpal.com/mercedes-benz-within-10-miles-of-sylva-north-carolina-28779 If you do not find a specialist, the other shops on the list will have excellent training and equipment, and will provide you with an honest quote and proven diagnosis.