I bought an OBD2 code reader for the 2005 Honda CRV and it shows P0325. On lookup it's an issue with the "knock sensor". Half the time the engine light comes on and half the time not - which is the reason I picked up the code reader. The car is running just fine. How important is it to replace the knock sensor? Perhaps the problem is just a loose connection to the knock sensor? Other thoughts? I see it's generally about $400 to replace $300 labor and $100 part.