I urgently request a NHTSA investigation into systemic coolant leaks, a dangerous safety defect in Audi vehicles with the 3.0L turbocharged V6 (EA839) engine. Affected models include the Q7 (my 2020 Q7 55 TFSI, VIN: [XXX] ), S4, S5, SQ5, A6/A7, Q8. These defects risk engine damage, sudden power loss, and catastrophic engine failure, endangering all road users. Many owners report premature failures of cooling components (water pump, thermostat, PCV system). Failures often occur post-warranty, costing owners over $3,000 for repairs. Online forums (AudiWorld, Audizine, Reddit) document these widespread defects. The class action [XXX] et al. v. Volkswagen Group of America, Inc. alleges water pump defects in EA839-equipped Audis (incl. Q7 up to 2022). Critical Safety Concerns: The primary safety risk from these coolant leaks involves: Coolant Ingestion: Coolant enters vacuum lines, mixes with oil (faulty PCV), or enters intake (failing intercoolers). Engine Malfunction: Ingestion causes misfires, drivability issues, and sudden power loss during operation. Catastrophic Engine Failure: Severe coolant ingestion can cause catastrophic engine failure, risking loss of control and collisions if the engine seizes/fails at speed. Sudden engine malfunction/failure while driving due to this systemic defect warrants immediate NHTSA investigation. Audi of America is aware. My contact (Mike, Ext. 43252) confirmed Audi is not addressing this widespread failure. Audi’s inaction necessitates NHTSA intervention for consumer and road safety. Affected owners urge NHTSA to: Initiate a formal investigation into systemic coolant leak issues and component failures in EA839-equipped Audi vehicles. Assess the safety risks, including potential engine failure and loss of vehicle control. If warranted, issue a safety recall for affected vehicles to prevent accidents and injuries. Public safety is paramount. Evidence indicates a defect compromising vehicle safety and reliability. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION