Thoughts on knock sensors..not nissan oem

[s13pignose]

I noticed a huge price diff b/w nissan knock sensors and say ones on ebay. Correct me if I'm wrong but the sensor it self is 100+, not including harness. If i'm looking at the right harness, courtesy nissan sells the KS harness for like 50 which I can live with. I've pulled my ecu twice both times I had code 34, even with fresh gas new dizzy cap and rotor, cleaned plugs.

Read in some posts that theirs a short in the harness itself going to the KS that can cause the code, even with the sensor itself being okay. Now is it the harness for the KS or a different wire?

Also read how much of a pain it is to change, so I'm thinking it would be better to replace both. Thinking of nissan harness to a non nissan knock sensor.

Anybody see any issues with that?

Thanks

[s13pignose]

Btw the sensor I'm looking at the manufacturer's PN for it is 22060-30P00 and for
240 SX, 91-98, 2.4L 4cyl.

Now the whole short in the wire issue I still don't understand, but how does it end up happening to begin with. I'm not looking to really patch anything up..rather replace with something new and try prevent it from happening again. If possible?

Whatever is causing my code 34 must've happened recently, cause I've pulled codes from my ecu before, and 34 wasn't one.

[drifter_for_life06]

IIRC, wouldnt a knock sensor not working properly or the harness not transmitting the signal correctly cause some driveability issues? like limp-mode?

[s13pignose]

I dunno, but my car has had issues with in past two months like randomly cutting off..stumbling rpms while driving. All this despite of things I've replaced like dizzy cap and rotor, coolant sensor..and spraying intake cleaner down my AICV hose to try and clean it out, cleaning my MAF. Fuel filter can't be more than 3 months old. Plug wires are good, and I cleaned plugs like 2 days ago which have probably 3 months use on em..not fouled. Tried listening for vac leaks and inspecting hoses.

I mean I dunno what else to do but assusme it is knock sensor. Only other thing I've talked to projectrdm about is my valve cover is leaking and was wondering if the gasket for the spark plug tubes was leaking two. I pull the wires out, and bone dry. Plugs are clean past the threads too.

[s13pignose]

Also this code 34 I assume that means I have nothing monitoring the motor for knock? Not that it's detecting knock. If that was the cause the ecu just retards timing w/o giving a code correct? I'm running 93 octane, so I guess I'm safe. Plus my ka is n/a with stock timing.

[drifter_for_life06]

id say just go for what you have found...if its cheap and works hey why not....if it doesnt work well...you're screwed out of what you got off ebay, but now you know. And try finding someone on here or another forum doing a KA part out. I'm sure someone has a useable KS they would be willing to sell. A lot of people dont even bother listing the Knock Sensor in total part out threads since not many people buy em, but its always worth asking the OP of KA F/S threads

[xsparc]

the ebay sensor will be fine, thats what i have.

as for the harness going bad... thats a whole nother mess. the section of the harness that gets shorted out (well at least for me) is the shielded section that runs from where it branches off near the TB to the ECU. Im guessing that moveing and bending the harness bundle that goes over the injectors caused a kink in the center wire and it eventualy pushed through the insulation into the shielding.

the easiest way to check for this is to unplug the ECU and the KS, the just meter the wires.

if it is shorted you are going to need to pull your harness apart, start at the KS side, and just look for a kink, wont be hard to spot once the harness is all aprt.

[s13pignose]

Cool. So just pull the harness, and if there is a short to ground I take it then I gotta unwrap the the harness and look for a break in the ground wire?

At least I know I can go with the ebay sensor.

Thanks

[xsparc]

Cool. So just pull the harness, and if there is a short to ground I take it then I gotta unwrap the the harness and look for a break in the ground wire?

At least I know I can go with the ebay sensor.

Thanks

uh... short means its connect to ground, open means there is no connection to ground



maybe you shouldnt do this yourself...

[Kaifd3s]

As for installing the sensor, I put mine in last week. It's a real pain putting it back on.

[s13pignose]

uh... short means its connect to ground, open means there is no connection to ground



maybe you shouldnt do this yourself...

Thought thats what i said lol. What i was getting at is from the post I read, there's like a bulge or break in the wire indicating where the trouble is right?

[s13pignose]

As for installing the sensor, I put mine in last week. It's a real pain putting it back on.


You take the manifold off, or worked around it lol? Think I'm gonna have to work around

[jskateborders]

IIRC, wouldnt a knock sensor not working properly or the harness not transmitting the signal correctly cause some driveability issues? like limp-mode?
Not limp mode, will just retard the timing, causing less power and worse gas mileage.

[Mangudai]

How can you tell if it went bad?

[slider2828]

Nope, I did it without taking off the sensor and it was like a 15 minute job.... on an SR I think same with KA.

Do it at your oil change, but take off your oil filter, reach up and unscrew the bolt. Not a big deal, a short 10 or 12mm wrench is best, not your standard length. You can get em at kragen for like 20bux for the wrenchs.

DO NOT overtorque these sensors as they can get too sensitive. Suggested torque is like 10-12 lbs, so that is just wristing the bolt not torquing on it. Check your wires too!

[DALAZ_68]

IIRC, wouldnt a knock sensor not working properly or the harness not transmitting the signal correctly cause some driveability issues? like limp-mode?

i always thought...no KS = car wont even start..guess i learned something new today...lol

[s13pignose]

Not limp mode, will just retard the timing, causing less power and worse gas mileage.

Hold up...thought thats what it does when it is working. When not working, it still pulls timing?

So say you have a situation causing detonation..but you fix..does the sensor sense that and bring normal timing?

BTW thanks for all the input guys

[Kaifd3s]

Nah i worked around the manifold. Plus, I did it from the top of the manifold. I scratched this shit out my left hand, but I got it on. I literally spent like 3 hours trying to get the bolt in the hole. It really helps having a wobbly socket and like a REALLY long extension.

ALI

[xsparc]

no KS = use of a special knock map in the ECU and gives a code
bad KS = ^
working KS = sex

[s13pignose]

LOl I would like to see the end results of me replacing it..I dunno if I'll notice an increase in mpg as I stay heavy on the gas..but I should be able to tell if it runs better which is most important to me.

[Sileighty_85]

Hold up...thought thats what it does when it is working. When not working, it still pulls timing?

So say you have a situation causing detonation..but you fix..does the sensor sense that and bring normal timing?

BTW thanks for all the input guys


Most knock sensors send a base or “no knocking” reference signal to the ECU.
If knocking occurs, the sensor detects the increased vibration and increases its signal to the ECU. The ECU then slightly retards timing until the sensor signal returns to the reference level.

If a temporary condition caused the knock, the ECU will set spark timing to the programmed advance. If the knock returns,
the ECU will cycle spark timing, advancing timing until knock is encountered and then retarding timing until the knock is gone.

[SILVIA_KIDs14.5]

You take the manifold off, or worked around it lol? Think I'm gonna have to work around
btw if you have a short to ground the sensor will not work properly that could be your first problem

[slider2828]

Shorting the sensor, just disables the sensor = no knock. That is it no big deal. If the car knocks it goes to a knock map and which usually retards the timing and maybe fuel trim. If you guys want to just really learn more visually, just look at ALL the threads Nistune is in. You will get the idea as it is a visual rom tune.... kinda...

KS is just a big microphone, if the ecu hears nothing, it knows nothing.....

[s13pignose]

cool thanx

[Chad4061]

i got my knock sensor off ebay and it had a 5 year warranty...havent had any problems thus far. As far as the installation goes it can be a PITA. I used the diy on nicoclub so i could change it w/o taking off the intake manifold which saves lots of time

[midnightouge]

What else can cause the ecu to throw code 34?

I have replaced the KS, tried installing a resistor, new distributor cap/rotor, water temp sensor, cleaned IACV, swaped MAF. Yet i still get code 34 and my engine jumps around once its warm.
Any ideas?

[Pacman]

uh... short means its connect to ground, open means there is no connection to ground



maybe you shouldnt do this yourself...

It could be shorted to power...

If the sensor hasn't been dropped from any distance, just replace the pigtail harness. Since the harness is like $50, I'd start with it AFTER making sure teh sensor just hasn't come loose off the block. I'm in this situation, gonna order my pigtail tomorrow from Nissan.