My car failed OBDII P0325 knock sesnor | CKT Malfunction

[Negative-Ion]

The mechanic said that the knock sesnor doesnt work right and it needs replacement. Ive also replaced two O2 sensors. Im now trying to change the Knock sesnor but i cant find where is located. My car is a Nissan Pathfinder 98 model. Im either blind or the knock sesnor is hidden somewhere where i cant see it. So im asking for help on my first post here, where exactly is the knock sesnor located on the nissan Pathfinder 98 model?

[NISTECH]

it is located under the intake manifold in the valley of the block.

To comment on your failure. I am a licensed smog inspector for the state of california. Here the knock sensor is not a reason to fail a smog inspection even if it stored a code because: The law states that if a code is stored in the system there must be a mil [malfunction indicator lamp] command being issued to turn on the service engine soon light. If the light is not on AND the SRT moniters have completed you will not fail for OBDII inspection. Although smog laws differ from state to state federal OBDII laws do not require or list the knock sensor as a requirement this is the reason it will not illuminate a SES light for a po325. The strictest emissions requirment in the country are right here in california but Newyork is the second strictest in the country. If I were you I would do a little bit of reasearch and find out exactly how the law is stated for obdII requirements in your state. Try to focus on the section of codes and mil requests. I bet you find the inspector is wrong or is trying to get the "upsell" as it is a very labor intensive job.