knock sensor

[charles ritter]

i have a 96 Nissan Maxima GXE im getting a p0325 knock sensor i tested it i unpluged the knock sensor harness and checked it i got 5 volts then pluged it back up then done the voltage drop test and got a 2.49 witch is good but i still get the p0325 code i am stumped does anyone have any ideas

Topic

[Richard Kirshy]

Have you checked the resistance of the knock sensor itself?

[charles ritter]

you cant check the resistance on a knock sensor it does nothing

[Timothy Salomon]

I think the knock sensor is either a capacitor, or more likely, a piezoelectric that generates an Ac signal when shaken. Tests of the sensor require an oscilloscope, so at this point the Diy’er is forced to just change the part. And knock sensors are cheap, around $30, but hard to access on FWD models.

[charles ritter]

mine is $102.00 ericthecarguy did a video on knock sensors i did the same test and acording to the test it was good but i still get the p0325 code

[Sam Roodman]

They are 125$ for the toyota 1mz-fe and that requires 2

Sent from my SM-N900V using Tapatalk

[charles ritter]

i just dont want to spend the money to find out it wasnt bad and that it was due to something else

[Richard Kirshy]

My mistake I meant to say voltage.
Which can be tested.
As to the cost:
You really need to do some power shopping

And if it is any thing like my knock sensor in location (mounted at the bottom of the valley pan under the upper and lower intake manifold)

Easy way is to simply relocate it to the top of the engine

Attachments:

• KS.jpg
• KS1.PNG

[Timothy Salomon]

If you think the sensor is good, and you know the 5v power feed to vehicle metal is good, do you also have 5v between the two pins on the connector? Either way, at least one of the wires is good.
Now, for a professional mechanic, using a scope to capture the waveform, compare it to a known good waveform in the FSM, and then you can replace the pcm. Without a scope it’s time to guess and change parts. I’d rather not spend money on parts until I’ve cleaned connections, wiggled terminals, and cleared the codes.
What if it’s a motor mount and the engine is actually shaking? The electrical system might be fine, telling us the engine is shaking more than normal.

[charles ritter]

thank you all i went ahead and got a new one because i think it may be a intermediant problom it comes and goes

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