The engine P0620 Code has various meanings and you should not accept any meaning of the code or any false meaning like automobile dictionary meaning. You will get the right meaning of the code from your car manufacturer. Different car manufacturers also give the meaning of the same engine code what are not allowable. You can find the real meaning of the code from the car engine’s manual if you know the name of the car and know the name of the brand manufacturer. If you do not know the process of solving the car’s engine, you must not try to fix it. Rather than, you will hand over the car to expert automobile engineer.