it is most likely the magnet in the cam sprocket. I had the same issue. i replaced the cam sensor because thats what the code said then the code didnt go away so i have to replace the cam magnet. you can use JB weld to get a new magnet in there if you take off the cam sensor and line everything up. I didnt do this as my timing chain was near failure and the damper had failed along time ago.
There was more than an inch of slack in the chain. i had a hard time putting the new one on because there was no slack.
The magnet broke out of its plastic housing which may still be in the camsprocket make sure you remove it if you are going to JB weld a new one in
The destroyed damper. the engine had only been rebuilt 56k miles before but i doubt they took the timing cover off to replace anything.