The engine P0377 Code comes for the cause of the car engine problem and you should identify the real cause of the car engine. The engine code is necessary thing what is used for solving the car engine problem. You should check the symptoms decreased engine performance and engine may not start to know the cause of the car engine problem. There are some common problems what can be started due to the engine problem and those are crankshaft Position Sensor (CKP) failure, fuel injection control module (FICM) failure, powertrain Control Module (PCM) failure and wiring issue. A test drive is recommended.