The diagnostic code P0344 OBD2 basically means that the signal coming from the CMP sensor (Camshaft Position Sensor) is presenting faults or it may not be present. This fault is originated in the electrical circuit, and is intermittent. In other words, this failure is not constant. The CMP sensor (Camshaft Position Sensor) is located in bank number 1; bank number 1 is the side of the engine where cylinder number 1 is.
The Camshaft Position Sensor (CMP) is used by the PCM (Powertrain Control Module) to indicate when the signal from the CKP sensor (Crankshaft Position Sensor) is correct and when the signal sent by the CKP sensor (Crankshaft Position Sensor) is synchronized with the cylinder number 1, which is used for the timing and, similarly, is used for synchronization of the fuel injector.
DTC Codes such as P0340 and P0341 may be present along with this DTC code. But you have to take into account that these codes differ so much in the time that the problem lasts, as well as the electrical failure that the sensor, circuit or even the motor can have.