Diagram of the knock sensor on a nissan quest 1998

the sensor is located on the trans housing above the right axel where it inters the trans

go here: http://parts.nissanusa.com/nissanparts/index.cfm?bodyColor=&trimColor=&BODY=W&ENGINE=VG33E&EMISSION=GXE&TRIMLVL=GXE&TRANS=AT&action=replacement&groupid=D&sectionid=226&partcode=22060P&jointvehid=10541&makeid=25&siteid=14&illust_seq=01

This will show you the diagram of where it is located...auto parts stores carry this part too so don't think that the price you see there is final.
Hope this helps you

Its located in the front engine,where there is the cooling temp sensor,next to the fuel filter..

p0325 is the "knock sensor" code.

it is buried under the intake manifold. But ignore the knock sensor code, it means absolutely nothing. It will not resolve any issue you have. The KS code is usually the result of a broken engine mount.

go here if you have any issues.

http://groups.yahoo.com/group/villagerquest/

it is under the lower intake manifold.

you have to remmove the intake and it is on what looks like a bracket that bolts to both heads is the knock sensor

On the Nissan that code means you have a short in the knock sensor circuit or you just need a new knock sensor.

It is under the intake manifold, in the valley of the motor, can be difficult depends on your skill level.

I know that the knock sensor for a 1998 Quest with a 3.0 is located on the passenger side of the engine compartment under the intake manifold. You should be able to find the wiring and connector next to the intake manifold. To access the sensor, you have to remove the upper and lower intake manifold. The sensor is on the block between the heads. Hope this helps.