NHTSA Complaint #11517566 — 2023 GENESIS G80

My TWO WEEK OLD 2023 Genesis G80, which has less than 1000 miles on it, lost all motive power (i.e. power to the engine) after driving for approximately four hours. We were sitting in stop-and-go-traffic on the George Washington Bridge in New York, with the engine off (because of the vehicle's auto-off function). When the car ahead of us moved, I lifted my foot off the brake pedal, pressed the gas, and the engine immediately failed to respond, sputtered, and stopped. After about a minute, we were able to restart the engine and continue driving. We drove for another approximately 1.5 hours, including a short rest stop. Then, while traveling at highway speed of ~75 MPH in the left passing lane of Interstate 84, the engine again lost all motive power. When the accelerator was depressed, there was no response. I was able to (narrowly) safely maneuver (drift) my car into the breakdown lane, and when the car finally stopped, the engine stopped entirely (it had been sputtering while coasting). After a few minutes, I was again able to get the car re-started, and we were able to drive another five minutes, before the car again lost all power, forcing us to drift off the interstate into the breakdown lane, near the beginning of an off ramp. I saw that there was a Hyundai dealer approximately a mile off the ramp, and so tried to reach the dealership. The car lost all engine power multiple time, just trying to reach that dealership. In the parking lot, we were unable to even start the engine any time in the next three hours. Most concerning, after having the car towed to a Genesis dealer, the dealership reports that the car showed NO FAULTS OR ERRORS, and they are completely in the dark as to why the car lost all power, both while stopped, and at highway speeds, and failed over and over. The lack of any reported faults or errors is both baffling and extremely worrisome. The dealer "hopes" but is unsure, that replacing the GDI fuel pump will resolve the issue.