Nissan Repair: Camshaft position sensor, camshaft position sensor, camshaft

Question
i got the code PO340. How do i know its only the sensor that needs to be changed or if the problem is electrical or just coming from another source? I would take it to a mechanic but they seem to be charging an arm and a leg everywhere. If possible could you tell me what a reasonable rate to diagnose and execute the problem would cost? Thank you

Answer
Walter,

The cheapest way to know is to inspect the harness leading to the camshaft position sensor.  If the harness is fine replace the sensor.  Diagnostics start at $100 bucks and up.  The part is pretty reasonable at rockauto.com or courtesyparts.com

If yours has a distributor then it is this that is the camshaft position sensor and that is what would need to be replaced.