you can see all your issues if you use a good scan tool to check your car, knock is caused by
1 - lean burn
this can be from a clogged injector, leaking intake manifold or even bad valves in some cases.
2 - carbon build up
this can be from the engine running dead cold all the time and eventually building up cakes of hard coke in the combustion chamber - these then glow hot and cause knock.
3 - bad timing control
SO - all in all - its not a simple answer of "yeh kardo set hojaega"