ELECTRICAL SYSTEM,ENGINE,FORWARD COLLISION AVOIDANCEThe vehicle experiences a sudden and dangerous malfunction while driving. Without any prior warning, the vehicle begins to shake and then immediately brakes on its own, coming to an abrupt stop in the middle of traffic. Only after the vehicle has already braked and shut down does an “Engine Control Error” message appear on the display. There is no advance alert and no time for the driver to react or move out of traffic. This is exceptionally concerning especially as this vehicle was being used a primary mode of transportation for my 2 young toddlers who were present in the vehicle during these failures. The vehicle was purchased directly from Porsche as a Certified Pre-Owned vehicle in June 2025, and was represented by Porsche as having passed all safety and mechanical inspections at the time of purchase. Despite this, the vehicle has continued to experience catastrophic failures. Following the initial shutdown incident, the vehicle was towed to Porsche for service on September 2. Porsche stated that the issue had been repaired and assured that the vehicle was safe to operate. However, on September 29, the same failure occurred again. The vehicle shook, abruptly braked in active traffic, shut itself down, and only then displayed the engine control failure message. This shows that the underlying defect was not corrected and continues to pose a serious safety hazard. The problem is severe, unpredictable, and reproducible. It places the driver, passengers, and surrounding motorists at immediate risk because the vehicle becomes immobilized in traffic with no prior warning and no ability to pull over safely. The vehicle has been inspected by Porsche technicians, but the root cause remains unknown, and Porsche has been unable to provide a successful repair or assurance of safety. This pattern strongly indicates a critical defect in the engine control or power-management system that renders the vehicle unsafe for public road use.