knock Sensor Relocation

[ptbo_hunter]

Hey Guys,

I have a 2003 S/C XTerra. I have noticed a lack of power. I used a buddies ODBII code reader and it threw a P0328, which I think is the Knock sensor. I reset the computer and will re-check it later in the week, just incase it was bad gas. From what I've read it's a real B*tch to replace. I found a mod on another forum and was wondering if anyone has done it and their success? Here's the link, it was done on a frontier but I understand they have the same engine.

http://www.clubfrontier.org/forums/f46/ ... ow2-48473/" onclick="window.open(this.href);return false;


Thanks in advance!

[Scotto]

Hey.

Yup - lots of us have done it. Some of us have even written about it. For your year of truck no less:

http://www.cntc.ca/phpBB3/viewtopic.php ... relocation

From what I understand, on an SC engine, it might be better to just put a resistor on the line instead of installing a new KS. Or, if putting a new KS in, sandwich it on some rubber matting. It's just that a KS is about $80- off ebay, and a resistor is about .8 cents at crappy shack.

Here's a link to a non-SC truck. It's the same deal, pretty much:

http://www.cntc.ca/phpBB3/viewtopic.php ... ock+sensor

[medic]

we need a mod day this spring/summer. I still have my replacement knock sensor and need to install it.

[studum]

OP - I recommend you sign up as a premium member. There's an excellent walkthrough in the how-to section for exactly what you want to do on that engine (amongst other things) but you have to be a premium member to see it. As a bonus you can have access to your factory service manual (worth the membership fee alone). Plus, you'll be supporting the club

Good luck. If the PO of my truck didn't have it done the way Nissan wants it done I would have done the relocation or resistor as well. I'm sure he would have liked to have known about this lol, his repair bill was in the $1,000 range I believe (the sensor itself was about $150). I read about this before I bought the truck, and was kind of glad to see the replacement receipt to be honest.

Good luck with whatever you decide to do. The P0328 does affect the performance of the S/C engine big time from what I hear. The N/A's not so much.

[ptbo_hunter]

Thanks guys! Sorry, I'm not a premium member yet. Is the write up on here basically the same as the frontier write up? What is the therory for using the nissan maxima KS?

[Scotto]

Thanks guys! Sorry, I'm not a premium member yet. Is the write up on here basically the same as the frontier write up? What is the therory for using the nissan maxima KS?

It's probably pretty close. It's two wires that feed the KS, so it's just about finding them and then attaching the new KS to some part on the engine.

The maxima KS is probably the cheapest from Nissan. I would just get one off ebay - save a bundle of $.

[ptbo_hunter]

I found this one on ebay. Does it sound kind of cheap? In the title it says it fits but under the list of vehicles it doesn't list the XTerra?

http://cgi.ebay.ca/NEW-Nissan-Altima-Ma ... 20b70d7563" onclick="window.open(this.href);return false;

[re-ride]

there is quite a variety of ks available if you search for 1999 nissan maxima ks, costing from 10 to over 20, how do you determine which one to get, also can the harness be purchased off ebay as well, or is it necessary to go through the dealer?

[Bow_Tied]

Or, if putting a new KS in, sandwich it on some rubber matting.

I have not had to deal with this before, so maybe this is a dumb question set.... I thought the knock sensor detected detonation in the engine and retarded the timing to prevent engine damage. Mounting it on rubber would reduce its ability to do this, no? Or is it that the sensors are too sensitive? I read about relocation and presumed that was for ease of access since the sensors fail on occasion. Is it really that they don't fail and are just too sensitive or do they fail and fail in safe manner?

Just curious.

[re-ride]

some people have said that oem nissan ks rarely fail but the connections do, just not sure which connections to check, also to clean the ground connection on the rear passanger side of the sc

[re-ride]

ive found a ks on autopartsway for about $80 but i'm not sure what you call the harness unit to find it as a part, any ideas? The SKU number i have does not register at autopartsway

[Nd4SpdSe]

Don't spend the $250 on an OEM Nissan sensor. It's either way too sensitive or mine was bad out of the box, cause it was getting many, MANY false knocks. Tried sqeezing it between rubber and it helped, but didn't go away. I unbolted it, wraped it in foam, tied it to a wire harness and it was STILL detecting knocks. My gas milleage was horrid and I could barely afford gas to get to work. So at that point I pulled it out and replaced it with a resistor. Been running like that for over a year now. I'd perfer to keep the KS, but it's just wasn't worth it. Get the cheapest one you can find and use that. At some point I'd like to try one from a different Nissan, even get an Ossiliscope and use that to test it out. Ideally at some point, I want to run a piggyback engine management.

[Bow_Tied]

Is the engine from the x different than the early R50s? I don't hear of those having KS issues on NPORA...

[Nd4SpdSe]

Ya, good question, but even then, it's really only us S/C guys that report this problem. I'd like to think that the N/A guys have the same problem, but it's not nearly as obvious since we're not only affected by retarded timing, but limited boost as well, so our power drop off is huge incomparion, but it's worth looking into, I should check the FSM and compare the diagnostics for the KS to see if the resistances are the same,

[Simon]

Ron, the engine isn't really different, other than placement of some accessories. But the Knock sensor isn't really a problem on the R50's for some reason. I'm not sure if it's a different sensor, or in a different location, but it's not an issue. I've run codes on Pezzy's truck and nothing came up, but on my X I had the knock sensor code until I relocated and replaced it.

[Bow_Tied]

Is yours S/C Simon?

I keep seeing the KS issue crop up and have to wonder what the deal is. If a KS from a 96-99 R50 didn't help I have to wonder if it is the ECM in the X that is the sensitive part.... just wondering aloud...

I don't have an X so why am I bothering talking about this? Well, I am starting to shop for another vehicle. I like the 02-04 Xs but am concerned with this issue (and a couple of others). Not sure I can afford a newer X.

[Simon]

Mine is not S/C, but I replaced the sensor anyways. It seems my acceleration has smoothed slightly, with a slight increase in power, but no huge difference.

To be honest, the knock sensor isn't a huge issue, and you can have yourself fixed up for like $20 if you buy an aftermarket sensor. Rockauto.com has them cheap, and that's where I got mine.

[Simon]

Apparently I lied. Pezzy's truck does have the knock sensor code, according to her Scanguage. So maybe they aren't different?

[Pezzy]

Apparently I lied. Pezzy's truck does have the knock sensor code, according to her Scanguage. So maybe they aren't different?

THE LIES AND UNTRUTHS!!!!!

Yes, I have had the code come up a few times since I got my ScanGuage.

[Nd4SpdSe]

If it's acting funny doesn't meanit's throwing a code, just means the sensor is out of the valid resistance range. I've never gotten a code after I replaced it, but it still acted wonky alot. You could feel it, and Jayman describes the same symptomes. I would trust Simon and Pezzy to have enough vehicular and time behind the wheel of their trucks to feel if anything is a miss.I will say since I found out that the A/C is on with the defrost, I've been driving around with the defrost off (cause it's almost always on) and man does the truck feel better.