The engine P20D6 Code is related with the car engine and it needs to fix sooner if you want to drive the car without any problem. This code has different meanings but without accurate meaning of the code, it is impossible to fix the car engine. You should read the manual of the car engine and you will get the real meaning of the code for solving the car engine. Do not drive the car until the car engine is fixed. You should use the manufacturer meaning. You may find the meaning from car engine manual or get the manufacturer name and car model for solving the car engine.