I searched on google to no avail for the location of the knock sensor. I found it myself and thought I would help those in need since later model Hondas seem to require the removal of the intake manifold.

The knock sensor is located directly above the oil filter. It requires a 24mm socket long enough to cover the end. There is no need to remove anything else in order to access it.

Obviously, I can't diagnose the specific reason your check engine light came on, but my knock sensor simply broke in half requiring a replacement - $130. A common problem I saw in my search was wire faults needing no replacement.

Good luck.

 

130 is too much they are more like $100

 

Maybe you can buy mine? I'm not using it. lol