NHTSA Complaint #11690498 — 2019 MAZDA CX-9

1. What component or system failed or malfunctioned, and is it available for inspection upon request? ANSWER: Engine failure due to overheating. 2. safety & indicators: ANSWER: During evening rush hour traffic on a 3 lane highway my car went into a form of engine power saving mode while i had children in the vehicle; this was almost catastrophic form my family and the other vehicles around me. there was NO warning. there were no previous issues with my vehicle, this was unexpected. 3. technician review: this is a known issue with no warning: The technician inspected your vehicle and found a concerning issue with the engine overheating. They scanned the vehicle and found a trouble code P111A, indicating the engine coolant reached a temperature of 251.6 degrees Fahrenheit, forcing the engine into limp mode. Based on their experience, the technician believes the engine likely reached much higher temperatures, potentially causing internal damage to the engine block. After a thorough inspection, they found no external coolant leaks, but upon using a digital borescope, they discovered evidence of coolant entering and being burned off in Cylinder 3. Given the severity of the issue, the technician recommends replacing the entire engine to ensure the long-term reliability and extended life of your vehicle. Services completed: - Scanned vehicle and found trouble code P111A - Inspected engine and found no external coolant leaks - Used digital borescope to inspect cylinders and found coolant entering Cylinder 3 Recommendations: - Replace the entire engine