The contact owns a 2019 Hyundai Veloster. The contact stated that while driving at various speeds, the engine would overheat and the vehicle would stall. The vehicle was taken to the local dealer who diagnosed that the engine needed to be replaced. The engine was replaced and failures were remedied. Later while operating the vehicle the contact would become ill and had experienced dizziness and nausea which required medical treatment. The contact was diagnosed with high carbon monoxide levels. The vehicle was later taken to the local mechanic who informed that the carbon monoxide levels inside the cabin of the vehicle were high. The cause f the failure was not determined. The manufacturer was notified of the failure no assistance was offered. The failure mileage was 42,000.