Encountered P0327

[csprinkle]

Hello, on day two of my road trip down to Cali here. Seemingly out of nowhere I got a P0327 code, so I searched this code up in the forums and it brought back no results so I assume this isn’t a common issue. Engine runs fine, been around 18-19mpg with no stutters, rattling, knocking/pinging, etc. the whole way. 

 

I cleared the check engine light but it came back the next time i started it up about an hour or so later. I do have P0420/P0430 and P0740 as well so those could have triggered it. 

 

Not sure if anyone would be able to provide much help given that it could be as simple as a loose connection somewhere - but all suggestions are welcome.

[Slartibartfast]

The knock sensor code doesn't mean that the engine is knocking. If the computer hears something it doesn't like, it pulls ignition timing until the noise goes away, but it doesn't tell you about it. The knock sensor code means the knock sensor isn't working. The manual says to check the sensor (should be 500-620k ohms), check the harness, and loosen and retighten a couple of grounds on the engine. Diag starts on EC-320 of the '02 manual.

 

The catch is that the knock sensor is under the intake manifold. Unless there's a VQ-specific shortcut that I'm not aware of, or you have an exceptionally cooperative pet rat, you'll have to remove the manifold to access the sensor.

 

I had a knock sensor code on my '93 a while back. Turned out the sensor was bad.

 

Unless you hear pinging, I would ignore it until you're back home. The knock sensor is there for emergencies, and not used in normal operation. (I have wondered if the computer might pull timing out of caution if it knows it's got a bad knock sensor, but I have found nothing in the manual to support this.)

[CALPATHY]

There are couple or work arounds if you find the knock sensor is bad:  1) splice in a resistor but I don't remember which one, should be searchable, I did that as a quickie to pass smog  2) relocate the new knock sensor on top of the engine (which I did eventually) I think instructions searchable here as well.

[csprinkle]

Thanks for the suggestions, I will have a look when I'm back at home!

[csprinkle]

Sorry for the dead-end thread  - this issue resolved itself on its own. I believe a loose connector has probably jostled itself back into place

[adamzan]

The early 2000s knock sensors were notoriously bad on the Nissan trucks/SUVs. I've replaced probably 10 on the various Xterra/Frontiers that I and family/friends have owned.

 

You might get lucky but it'll probably come back.