NHTSA Complaint #11701206 — 2015 HYUNDAI SONATA

The engine/powertrain on my 2015 Hyundai Sonata (VIN: [XXX] ) has failed due to extremely low compression in all four cylinders, causing severe misfires, hard starting, loss of power, and intermittent rattling noises, and the vehicle is currently available for inspection at the Hyundai dealership. This failure created a safety risk because the engine hesitates, struggles to start, and can stall or lose power during driving, which could lead to a loss of control or an inability to accelerate in traffic. The problem has been confirmed by both an independent mechanic and the Hyundai dealership, who documented low compression across all cylinders. The vehicle has been fully inspected by the dealership on Hyundai’s behalf after I opened a case with the manufacturer. Prior to the complete failure, the car showed warning symptoms such as repeated cylinder 4 misfires, rough starting, reduced power, rattling noises on startup, and the check engine light appearing several times beginning earlier this year. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)