I am trying to fix up a few things on my son-in-laws 2000 Xterra with the 3.3 litre six. He his not very mechanical, but trys hard and is extemely innovative. I have been working on cars for over 45 years.

DAY 1: - Today we changed the last of the plugs, good olde #6 which had been in there for 120k miles (hint - go ahead and take the hood off). Then we replaced the faulty harmonic balancer (which had been mis-diagnosed as a rod knocking); I feel like I have been lifting weights all day, non-stop. To keep from getting bored, we fixed the faulty evaporator cooling fan (which is a bear to get to) in our spare time, and then recharged the AC in between rain showers. The TPS we will adjust tomorrow; it is throwing a code, but seems to be working perfectly on our scanner.

My question is this: After doing all of the above, the Xterra now idles smoothe as glass, and runs well. All of the knocks and rattles are gone, and yet after two miles it threw a code for the Knock Sensor at 7 mph. It was probably when he bogged the engine leaving an intersection, but I cannot prove it. Anyway, how hard is it for a fairly experienced mechanic to change the knock sensor. And is the knock sensor really the problem.


He lives in Austin, Texas and to get an inspection sticker all lights have to be off and they will probably run a sniff test.

Thanks in advance. ~ ~ Logger

Unless he has a supercharger, then from what I'm reading and have read, it's no major concern. I know a few guys on here have been riding around with that code for quite some time now.

Here are two threads that may enlighten you a bit on the knock sensor issue:

http://www.clubxterra.org/forums/showthread.php?t=3029&highlight=knock+sensor

http://www.clubxterra.org/forums/showthread.php?t=2799&page=4&highlight=knocking

Our "technical staff" per se, will usually check these forums in the morning times and they can give you a lot better info. But if you ever need any help with how to tear something up... then I'm your man! :mocking: hahaha

HI Drake,

Thanks for the reply and the help. The problem is that they won't let it pass inspection here with a light on. Their motto is "Keep Austin weird" and I have never doubted their sincerity.

So I either replace it find what it causing the code and fix that.

Again thanks ~ Logger

Hmm, well it was my understanding that the knock sensor code generally doesn't trip the light on these rigs. Are you sure there wasn't another code in there?

myself and a few others have been running with the knock sensor code for years and no CEL
what exact code is it throwing?
im in houston so i got the same inspection as you do, but with no CEL its a non issue for me

As has been said the KS doesn't trip the CEL. A bad KS is common on these vehicles. You have a couple of choices ... 1 swap out the KS with a new one, 2 ignore it as it doesn't trip the CEL, 3 bypass it using resistors (560K ohm), or 4 using a Maxima harness mount a new KS somewhere more convenient.
The KS is in the valley under the lower intake manifold and is quite a lot of work to replace.
If the vehicle is still showing a CEL then there is something else causing a code (I reread your first post and it is likely to be the TPS).

Ricer-X and K-One,

Thanks for your replies. We were trying to set the TPS voltage last night but there was too much rain. We were on our way out the door this am when I decided to check the board. BTW, is Ricer-X as in Rice U?

Again thanks ~ ~ Logger

lol, naw
Ricer-X as in Racer-X(from speed racer) except i used to drive a modded civic which ='s ricer, Ricer-X is my name on every forum im a part of, lol

Gentlemen,

Thanks for all of your help. The two codes we were seeing were 0325 - knock sensor and 0120- TPS.

The Haynes book had a rather complex method of setting the TPS, but I had read somewhere on this board to just set the TPS to between .45 and .55 volts. Setting the voltage to .5 volts solved the problem, and now the timing is back where it should be, so apparently we were in the limp mode, as the Xterra is running much better.

Strangely, there have no more knock sensor codes now that the TPS is correctly set.

I will now get back to the AC problem if the rain stops.

Again, thanks to all !! ~ ~ Logger

twas our pleasure

glad you figured it out....

Hmm, I still need to go through my TPS since the flood. I've got a TPS closed switch code, TPS open switch code, and some others. Who knows if the voltage is right. I should get on that I suppose.

I HAVE A SPARE TPS, UNUSED
id sell it to you 1/2 price if you end up needing one
as of this moment, i wasted $100 on it, you can have it for $50 if you need it

I HAVE A SPARE TPS, UNUSED
id sell it to you 1/2 price if you end up needing one
as of this moment, i wasted $100 on it, you can have it for $50 if you need it
Hey, thanks for the offer. I'll keep that in mind when I get to looking into this.