I have the 97' SE with 120k miles, auto
the engine light is on for a while, I scanned it.. it's P0325 knock sensor.

I ordered one from ebay (not Nissan). replaced the factory one (cracked already).
but after 100 miles, the code come up again, and can't be cleaned.

anyone know something about it?

Thanks

 

Check the sub harness for the KS for conductivity/wear. Check the shielding on the wire for splits and breaks. Mine was falling apart, replaced it and have had no problems yet.

Also check the resistance of the sensor itself. Somewhere on here there's a thread that says what the reading should be, otherwise I think it says in the FSM.

Oh, and if there are any other codes take care of them first.

 

Check the two ground connections at the front of the intake manifold, they are part of the circuit.

 

Good point

 

P0325 (DTC0304) Will not set a check engine light.

Was there another error code present as well?

 

No, that's the only one.
I erased it, then it come back around 100 miles, sometimes it disappeared by itself, but will come back again.

I can use the scanner to turn the engine off, but not able to take the code out from the reading.