The vehicle was being driven on a public road, going roughly 45mph. I felt a very harsh studder/clunk and completely lost responsiveness from the accelerator. There was no throttle response even pumping the pedal all the way to the floor. I was able to coast to a parking area and make a safe stop. Once I was stopped, I turned the car off, back on again, and it got me the rest of the way home. This was the most severe instance of the problem, but both primary drivers of the car have experienced the accelerator going unresponsive at different times. Since this was a severe safety related concern, we took the car in for service at the dealer, but were told they were unable to reproduce the problem and did not make any repairs. We provided the dealer with a video we captured toward the end of the latest incident, but they haven’t been able to find any cause. There were multiple warning lights on the dash, but no codes were stored. We did have another warning light for a brake system error, but there was no code stored and the dealer was unable to located the source of a voltage anomaly in the parking brake system. We’ve taken it in to another dealer service center for additional diagnostics but the original shop is refusing to provide the complete details of any diagnostics and corrections they have made, so we don’t have the original data that was pulled from the car.