replacing my knock sensor cured about 75% of my knock issues, It is alittle bit of a pain, it's on the back of the block under the head. I had to remove my intake manifold bracket to be able to get leverage on it, hard to get any kind of decent torque on the wrench due to the screwed up angle it will have your arm in. good luck.

A picture from when I did mine, tis is what a bad knock sensor will look like: