2026 Mazda CX-50

I parked this hybrid rental vehicle on a steep street facing uphill and remained in the car with it on for about 15 to 30 minutes. When I put the vehicle back in Drive, released the brake pedal, and pressed the gas pedal to drive away, the car quickly free-rolled backwards. There was no throttle response, and I had to quickly brake to stop the car from its quick backwards descent. Multiple attempts to correct the issue, including various combinations of placing the car back in Park and back in Drive, engaging the electronic parking brake, etc., had no effect. There was no throttle response at all when in Drive, and no ability to control the free-roll of the car after pressing the gas pedal when in Drive without braking. I even tried placing the car in Reverse, and this allowed me to go backwards at a controlled speed instead of free-rolling, but Drive only initiated an uncontrollable backward free-roll. Note that the hybrid vehicle was on, but the engine did not sound like it was running, and I believe it was in electric mode while experiencing this issue. There were no warning lamps, messages, or other symptoms of problems prior to or during the issue. Over the course of these various attempts I rolled backwards several car lengths. Had there been a vehicle or person behind me, there would have been an accident. I eventually placed the car in Park and turned it off and left it there. When I returned about 2 hours later the vehicle behaved as normal, and the issue was never experienced again while I had the rental car. Since this was a Budget rental car, they would need to be contacted about any availability for inspection. I did not report the issue to Budget or to Mazda. This issue concerned me enough to report it directly to NHTSA.