The engine failed (melted piston) such that I had a sudden lose of power while driving down the expressway. This resulted in my vehicle speed going from 70 MPH to 30 MPH. This resulted in my having to get to the shoulder of the road as quickly as possible to get out of the way of traffic. The vehicle was driven to the dealer (i.e. limp home mode). DTC’s P0304 and P0302 were present. The dealer diagnosed the failure of the engine due to a melted piston. This resulted in the vehicle needing a complete engine replacement. I sold the vehicle as is to a scrap yard. The vehicle was running normally and there were no warnings of any kind leading up to the incident.