The contact owns a 2018 Ford Escape. The contact stated that when the vehicle was started, there was an abnormal rumbling sound coming from the engine compartment, and the check engine warning light was illuminated. The contact stated that the vehicle accelerated normally, but while the vehicle was idling, the contact observed a rumbling sound coming from the engine compartment. The vehicle was taken to an independent mechanic where it was diagnosed that the spark plugs needed to be replaced. The vehicle was repaired but the failure reoccurred three days later. The vehicle was taken to the same independent mechanic where it was diagnosed that the cylinders needed to be interchanged. The vehicle was repaired but the failure reoccurred five days later. The manufacturer was notified of the failure. The failure mileage was approximately 45,000.