Engine Light On?

[Savage420]

Well guys my engine light has been on for about 6 months now and its started to piss me off just a lil. So i finally got my scanner back and hooked it up to reveal one DTC, and it is: P0332 Knock Sensor 2 Circuit Low Input (Bank2)

 

So what dose this meen? Big deal or no big deal, also what do i need to fix or replace to make this code go away for good?

 

Will it be expensive or not and will i be able to do it as im pretty good at working on my own stuff.