Engine Head Gasket Failure problems of the 2016 Chevrolet Sonic

Tl the contact owns a 2016 Chevrolet Sonic. While driving 15 mph, the vehicle shut off without warning. The contact also mentioned that the vehicle shut off without warning while at a complete stop. The contact took the vehicle to an independent mechanic where they diagnosed the vehicle and replaced the oxygen sensor; however, the failure persisted. The contact took the vehicle back to the independent mechanic on numerous occasions and had the thermostat and intake main gasket set replaced, and an engine tune -up; however, the failure continued. The manufacturer and dealer were not notified of the failures. The vehicle was not repaired. The failure mileage was 78,456.