The letter P of the car engine P1389 Code is powertrain and in the car engine, the powertrain is faulty. It is important to fix this part and in this task, it is not necessary to add anything in the powertrain or remove from the car engine or powertrain. The powertrain problem or the car engine can be fixed if you have the expert. So, if you do not know how to fix the car engine, do not try to fix it. The car engine code needs to know the right meaning and do not allow automobile dictionary meaning if the right meaning is found.