The contact owns a 2019 Mazda CX-5. The contact stated that while the vehicle was parked, the contact discovered an abnormal odor coming from the engine compartment. No warning light was illuminated. The vehicle was taken to a dealer, where it was diagnosed that there was a cracked cylinder head and that the cylinder head needed to be replaced. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 26,000.