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P0328/P0325 code. Knock sensor information.

399K views 270 replies 106 participants last post by  Paulsxterra4x4 
#1 · (Edited by Moderator)
I'm gonna make this a sticky cause its just talked about so much and recently there has been new information on this topic. If you are getting a PO328/P0325 code on your truck it is the knock sensor and it probably has gone bad but there are other possible reasons for getting the code. You might have gotten a bad tank of gas or your ignition system isn't working as good as it should. I would recommend you fill your tank with hi octane gas or gas treatment, run through that tank and check for the KS code again after you have cleared it and do other repairs before attempting the knock sensor replacement or by pass. Make sure your ignition system is working as it should. If after you have do all that and you are still getting the KS code your KS or harness might be bad. Its your choice to to do the replacement or by pass. We are trying to give you all the information we can to help you in your decision. There is not one good answer for your decision. Some decide to do the replacement. Some decide to do the by pass and some decide to leave it alone. Again the choice is yours!

It seems as though when your knock sensor goes bad the ECM will retard the timing to a preset position in order to prevent your motor from "knocking or pinging". This retard in timing will possibly reduce power and you will get slightly less MPG's but probably not enough to notice in the NA 3.3. In the supercharged 3.3 the ECM will put the truck in "limp" mode and you will notice a major reduction in power. This is to prevent your 3.3 from destroying itself. By doing the knock sensor by-pass you have now removed the safety from the system and will have to be diligent in what type of fuel you run and your driving habits. The knock sensor is attached to the cylinder block. It senses engine knocking using a piezoelectric element. A knocking vibration from the cylinder block is sensed as vibrational pressure. This pressure is converted into a voltage signal and sent to the ECM. Freeze frame data will not be stored in the ECM for the knock sensor. The MIL will not light for knock sensor malfunction. The knock sensor has one trip detection logic.

#1. Bad knock sensor won't set an SES light. The code was already there when the light came on.
#2. Bad knock sensor will possibly decrease fuel economy.
#3. Bad knock sensor will Possibly retard timing causing a slight reduction in performance but probably not enough to notice without monitoring live data.
#4. Knock sensor bypass should be done at your own risk especially with a SC Xterra.

The red arrow points to the location of the knock sensor:
 
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#152 · (Edited)
Getting ready to relocate the knock sensor and want to make sure that the wire I have shown in the pliers is the knock sensor wire.

This is the only wire in this shroud which has me wanting to double check since the vid on youtube I watched shows two wires in here. https://www.youtube.com/watch?v=d_JMJ1KRJwI

This wire seems to be larger in diameter and in the right location, but want to be certain before I cut.

Thanks





 

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#153 ·
Hi, I have 2004 sc x and mine only has 1 wire as well. Just finished putting everything back together tonight and relocated my KS to side of sc. Started up, not throwing any codes but did smoke a tiny bit. (Probably from cleaner). I ordered the Ks from online retailer and the one they sent was wrong plug, I went ahead and reinstalled old one. Will take it for spin tomorrow and repost. Hopefully I have all my power back.
 
#154 ·
Hi, I have 2004 sc x and mine only has 1 wire as well. Just finished putting everything back together tonight and relocated my KS to side of sc. Started up, not throwing any codes but did smoke a tiny bit. (Probably from cleaner). I ordered the Ks from online retailer and the one they sent was wrong plug, I went ahead and reinstalled old one. Will take it for spin tomorrow and repost. Hopefully I have all my power back.
Parts.com sent me the wrong Ks, they sent me a 00-02 Ks and i dont need. They told me to keep it and if anyone needs, I will ship to you for free if u pay shipping.
 
#155 ·
I just relocated my knock sensor. Got a new Maxima sensor and harness on ebay. $20. Cheap shit but it's now very easy to replace. I cut into my original harness and installed the new one on top of the intake manifold.

This is a 20 minute repair and IT WORKS. Or at least it seems to.. only drove it about 30 minutes after but no code p0325 anymore. It used to show up after 30 seconds...
 
#156 ·
Finally got my new sensor in yesterday and replaced it. Gotta drive it now and see if its changed. I do hear a small hiss and worried a gasket isnt sealed correctly. I am glad i decided to relocate, wasnt too bad taking everything off though other then lower intake being stuck on a stud. Hopefully its back to being normal again.
 
#164 ·
Hey guys I just bought a 2003 a couple days ago. When I test drove no codes were coming up. Then on the way home then check engine light came on so I pulled into O'Reillys and have them run it I'm getting a couple cards a catalytic issues on bank one Bank two and the
knock sensor. The dealership showed me the new distributor that they just replaced on it so I know that's not my problem. As long as the knock sensor just causes some poor performance and poor gas mileage I'm content with leaving it for now. My question is if the engine is experiencing misfires due to a blown head gasket if the knock sensor is bad what is still throwing up a car from misfires? As of right now the engine seems to be running great but the quality of the coolant in the radiator has me concerned I'm going to do a flush and so far I'm getting good clean oil so I don't think I have a reason to be concerned but I was just curious
 
#165 ·
I have had my 2002 Nissan Xterra SE for more than 15 years! I bought it in August of 2001. I love the vehicle. My Xterra was in excellent condition until I needed an oil change and took it to Mr. Tire late August 2016. Left my car for the service and had lunch. During lunch Mr. Tire called and said that the oil change was finished but they recommended a tune-up. Since I love my car I said yes. Long story short, Mr. Tire destroyed my car. Cylinders were not firing. They tried fixing it for almost two weeks and they called me to inform me that they will stop working on the vehicle and that their HQ will call me. Their insurance dealt with me and I had my car towed to another friend recommended mechanic and they fixed my Xterra. It is now running fine with no service engine soon light but the ride just felt different.

A month later I decided to buy an OBD reader just to see if everything is fine. The reader showed P0300 (misfires) and P0328 (knock sensor) errors. I found the fix on the P0300 on a website site by adjusting the idle speed screw (loosen a bit - a half a turn). I don't have car repair skills but since it was only turning a screw I tried it and it seems it has worked. The P0300 error is no longer showing.

I still have the P0328 error. Since I have settled with Mr. Tire I can no longer ask for them to pay for the knock sensor replacement. I should have bought the OBD reader before I settled. For the past 5 years I have been using premium gas so it is not a bad gas situation. I don't have the supercharged engine and also don't mind losing a bit of gas efficiency. The question I have is that will inspection pass my vehicle with the P0328 error? My inspection is in 3 months. I saw on another website that cleaning the engine ground bolt has cleared an P0328 error. Has anyone tried it and did it work?
 
#166 ·
Fair warning

This is just a heads up - I did the knock sensor relocation on my 2004 xterra (140,000 :eek:mi) against wise words. replaced plugs, wires, valve cover gaskets, and hidden hoses, etc. at the same time. Warning, when you put the fuel rail back on, do not damage one of the seals. Take it from me, you do not want to get back in there again after all that work.
 
#167 ·
Knock Problems in 2002 SE SuperCharged 4x4

Hi Everyone,

I realize this topic has been chewed through many times but I'm new to this and trying to find answers in these threads is tough.

I just purchased a 2002 Supercharged Xterra and sure enough, i'm getting the knock sensor code. It started as an SES light, when checked it showed 02 sensor AND knock sensor codes but now I'm ONLY seeing the knock. It definitely seems like I'm lacking some power, the milage has gone down (not by much but noticeable), when idling it misfires a bit and this could be unrelated but there is a slight burning smell after the engine warms up. The thing is in great shape with low miles and I'd like to fix whatever issues I have up front. I see a lot of information about what to do with NON-supercharged models but not a lot of specific advice for supercharged engines. I'd like to avoid the expensive knock replacement if possible but need some advice on if that's what sounds like needs to be done.

Thanks!
 
#168 ·
Hi Everyone,

I realize this topic has been chewed through many times but I'm new to this and trying to find answers in these threads is tough.

I just purchased a 2002 Supercharged Xterra and sure enough, i'm getting the knock sensor code. It started as an SES light, when checked it showed 02 sensor AND knock sensor codes but now I'm ONLY seeing the knock. It definitely seems like I'm lacking some power, the milage has gone down (not by much but noticeable), when idling it misfires a bit and this could be unrelated but there is a slight burning smell after the engine warms up. The thing is in great shape with low miles and I'd like to fix whatever issues I have up front. I see a lot of information about what to do with NON-supercharged models but not a lot of specific advice for supercharged engines. I'd like to avoid the expensive knock replacement if possible but need some advice on if that's what sounds like needs to be done.

Thanks!
Evening,

I am about 2 or 3 months post Ks relocate and everything seems fine. I do now run only 93 octane because of pinging after recloation and do occasionally get o2 sensor CEL (driver side, seems to be a Common issue; I normally reset it and it stays off doe weeks/month at a time. I did however go the long route and removed the sc, intake to get to ks but ended up just relocating. But did do water pump and timing belt to make it worth it. You can however relocate it without removing sc, if you can get another plug from salvage yard. Then just cut the wires otw down to ks then just mounting new one to the new spot.

The power gain from getting it fixed is astonishing. I also get 300 ish miles now to tank as opposed to 160 before fix.

In conclusion, I would do the relocate after getting a spare ks plug, then if you chose to address the o2 problem. If you wanted or plan to do the timing belt, then just do it mormally. My belt failed at almost 100k miles exactly. Also, if you live near my area, I wouldn't be opposed to helping you out, or if just Wana email me for quicker response, can provide phone in email for further help. Houston TX area sicrx69@aol.com
John
 
#170 ·
From reading through all these threads, I definitely like the idea of the bypass the best. Sounds like the quickest (and cheapest!) solution and seems most who have tried haven't had issues later on. Unfortunately, I'm not much to work on this kind of stuff by myself. I've got a regular mechanic I trust...I'm hoping I can convince him to help me run the bypass and take it from there. Or if any of you live in ME/NH area, would definitely be down to make it a weekend project!
 
#171 ·
The bypass mod really only requires basic low voltage electrical skills/tools like wire cutter/strippers and a soldering gun. If you can install a car stereo by following directions, you can do the bypass mod. From what I recall, identifying the wires was the most intimidating part. I suspected I had the right ones and then was certain once l I stripped the plastic loom back far enough to find those wires were isolated by their own insulated jacket. That left no doubt. From there it's simply cut the wires, leaving a few inches to the connector incase you were to ever want to return to stock, and tape them up to protect. Solder the resistor between the wires leading to ECU and either use electrical tape or shrink tubing before stuffing the connections back into the wire loom and use electrical tape over the wire loom where it was stripped back. It will look no different then stock once complete.
 
#172 ·
I personally wouldnt chose the bypass but i am not sure what difference is with relocate. As far as price, i just bought a cheap ks from net and works fine. I did do plugs before ks trying to narrow down issue. Not sure I mentioned it but i just relocated ks to firewall. I tried to put it on a bolt on back of sc but continued to exp my timing retarded and read it could be caused by noise in the bearings in the sc pulley. Firewall relocation did the trick for me.
 
#174 ·
Ive gotten the same error code after the little bypass hose by distributer split it stayed on for about 3 weeks reset ecm codes every few days then stopped been about a month never came back.now driver side valve cover gasket leaks so im ripping most of that off to change gasket should i change it since its not much work to do or just not worry about it motor has 280 000 km on it how long do they last
 
#175 ·
I had a 2000 xterra and a 98 pathfinder both with the vg33de engine and both had the p0325 code discovered (I don't know how long it had been on) when they both had a distributor fail and I was clearing the codes after replacement. the p0325 and 328 on US spec federal emissions vehicles should not cause you to fail inspection except maybe in some very strict states/counties etc. as it does not trigger the service engine light to come on, it just stores the code. (I verified by looking at both these aforementioned vehicles codes a few weeks later neither had a CEL but both still had p0325 pending and confirmed or whatever the other one that's "permanent" meaning the ecu has thrown the code 3+ drive cycles. but neither had a CEL and in fact the xterra passed inspection 2 weeks later and the print out stated codes present: p0325 vehicle passed and I asked the inspection guy how I could pass with a code he said as long as its not directly emissions related (knock sensor is not) and the cel is not on during inspection the code can be there and it will pass. he even said pending emissions ones would pass as long as all the other criterion was met. I did the mod to the x to fix the issue but it did not do much if anything performance wise still got 14mpg no matter what (whereas my newer 2011 x gets 18-20 which is great for this truck!) and still felt like it needed more power (but I think we can agree that the vg33de engine was a tank and will run forever but for sure needed about 50 extra ponies and about 50 more pound feet of twist per inch to be a serious truck engine, the 4.0 in the newer ones feels excellent and has tons of power low down and in mid range which makes driving more pleasant the older generation. I just ignored that code and kept going on my pathfinder and x and neither one had any issues due to it, no poor performance (relatively, the engine is a slouch anyhow) no worse mpg pathfinder got 14-15 and 16-17 on a down hill coasting with a tailwind but consistently from tank to tank 14-15 and the x stayed around 13-15 most tanks (I think it being taller, roof rack, with same power as the pathfinder and sitting up higher and weighing close to the same if not slightly more then the 98 pathfinder did, all played into that)

FYI I am in Tarrant county texas for anyone referencing emissions or inspection policies and this was between 2008 and 2013 so things may have changed (in my area I don't believe they have for this part anyway) and may also be different in other cities, counties, states etc.
 
#176 ·
I have 2004 Xterra. I had my car at a mechanic who told me I need a new head gasket. Never ran codes. Took it to another mechanic who said there is a leak but with she and 165k miles to trade in.

So I ran codes that neither did and I got the following errors
P0442
P0328
P0456

When I read about the knock sensor, I can now say in hind sight some issues like lower fuel economy and occasional smell of fuel. Neither symptom waa consistent. I have had to tighten fuel cap before too and engine went off.

So QUESTION: I am reading all these, and how do I know if I spend the money to replace knock sensor (btw neither mechanic mentioned this), spark plugs, and maybe gas cap that this will fix my problem or do I have a major engine issue?
 
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