The contact owns a 2015 Kia Optima. The contact stated that while driving at an undisclosed speed, the vehicle inadvertently lost motive power. The contact was able to coast to the shoulder of the roadway, where the vehicle was able to be restarted. However, several days later the failure reoccurred, and the contact heard an abnormal sound coming from the engine compartment, prompting the contact to discontinue driving the vehicle. No warning lights were illuminated. The vehicle was towed to the dealer, who diagnosed a nondescript failure with the engine. The contact was informed that the engine needed to be replaced. After investigating the failure, the contact related the failure to NHTSA Campaign Number: 18V907000 (Fuel System, Gasoline, Engine), but the VIN was not included. The manufacturer was notified of the failure, a case was opened, and the contact was referred to the NHTSA Hotline for assistance. The failure mileage was 96,000.