The contact owns a 2015 Cadillac Escalade ESV. The contact stated that upon starting the vehicle, there was an abnormal knocking sound coming from the engine compartment. The check engine warning light was illuminated. The vehicle was towed to an independent mechanic, who diagnosed a failure with the variable valve timing, resulting in damage to the engine. The contact was informed that the engine needed to be rebuilt or replaced. The vehicle was not repaired. After investigating the failure, the contact related the failure to NHTSA Campaign Number: 25V274000 (Engine and Engine Cooling), 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 89,000.