Cylinder head failure with power loss and misfires
ENGINE
22 NHTSA complaints · 2021-03 → 2026-06
“The dealer confirmed a catastrophic cylinder head engine failure. The vehicle had only 39,000 miles. After some investigating, there have been numerous complaints from vehicle owners with the same issue on the M264 engine (which is what my vehicle has)”
“While driving, my 2021 Mercedes-Benz GLC 300 began experiencing repeated engine misfires and rough running, accompanied by a persistent check engine light. These symptoms began shortly after I purchased the vehicle and progressively worsened over time. The vehicle exhibited…”
“While driving my vehicle on March 3, 2025 the check engine light came on. Additionally my vehicle began to shake. I was scheduled for a service appointment on March 5, 2025 and told the service department the check engine light need to be…”
“The contact stated that while driving at various speeds, the vehicle would lose power and fail to accelerate upon the depression of the accelerator pedal. The check engine light would appear on the instrument panel. Despite the failure, the vehicle would resume normal operation…”