The contact owns a 2018 Ford Escape. The contact stated while starting the vehicle, the engine was idling roughly. The contact stated that when the engine had warmed up, the rough idling stopped; however, when the vehicle slowed down for a traffic signal or traffic sign, the vehicle started idling roughly. The contact stated that the check engine warning light illuminated, and the vehicle was taken to a local dealer. The vehicle was diagnosed, and it was determined that there was coolant intrusion into the engine block, and the engine needed to be replaced. The vehicle was not repaired. The manufacturer was informed of the failure and referred the contact to the NHTSA Hotline to report the failure. The contact researched online and related the failure to manufacturer’s Customer Satisfaction Program: 21N12 Coolant Intrusion into the Engine (Engine and Engine Cooling). The failure mileage was approximately 61,000.