P0340 Code - Replaced CPS, code persists

My XJ is a 2000. CEL illuminates while on a 300 mile drive. I reach my destination without any noticeable trouble. My bluetooth OBD-II scanner shows P0340.

The next day it starts fine. On the way home the engine stalls out. It restarts and got it home.

I order a crankshaft position sensor and replace it. I clear the code. It starts and seems to run fine. CEL illuminates within a minute or two of starting the engine. P0340.

I have trouble starting the engine after it cools down. It takes a couple of attempts.

Any advice is appreciated.

Thank you.

Alex

So, upon further inspection, I heard a strange noise coming from the engine bay. I put a stethoscope to the camshaft position sensor.

Here's the recording...
https://drive.google.com/open?id=1fFCJz2VWVDnh8-fOeMM9MPJHm38BaU49

So, I replaced the camshaft synchronizer though I think only the sensor was bad.