The engine P0665 Code comes on the engine code reader by the testing the car engine. If the real meaning of the code is found, do not try to fix the car engine. You can read the automobile dictionary meaning of the code and it is p Powertrain Code Problem is related engine, transmission and emissions systems. 0 for SAE – Generic 6 for Vehicle Speed Control And Idle Control System. 6 for Control Module Throttle Actuator Position Performance and 5 for Park/Neutral Position (PNP) Switch Circuit Engine Torque Signal Circuit. You may get terrible problem in the car engine if the right meaning is not followed.