CEL Code 23 help!1

[Josh26]

just got a jdm p13
once in awhile my cel will pop and on it flashes code 23 which is knock sensor?
why would this be? when its on i have no vtec either.
any ideas

-josh

[NAiL05]

1. You have to wire in a knock sensor for p13.
2. Vtec will nevar work with a knock sensor code.