HI! I haven't posted for awhile, but now I have a reason. I am curious to see if I really need to replace the knock sensor asap or (if I can!) if it can wait or what the deal is. Have any of you had to replace yours? If so, do you recommend doing it yourself or having it done by the stealership?? I have a couple friends that could do it possibly, if I knew where it was! Any input would be great!!

Thanks!

the problem with the knock sensor at first wasnt that bad but now it is starting to hesitate real bad so i am going to replace it soon.... the part is 111 at autozone.com when i replase it i will take pics and do a write up on it so you can see if you will be able to DIY

Great! That's a few less than Advance quoted me...$117. Pics would be a big help when you do yours. Thanks!

parts prices also vary by region so keep checking around, for instance autozone might be cheaper were you are... just a little FIY also rockauto.com usually is the cheapest i find and they've shipped pretty quick for me. mine throws a code but i think ill hold on it till i do my timing belt because i have to take off a bunch of the same stuff.

well i also need to do the timming belt but i really dont know how to mess with the timmng of cars..... now i used to be able to time bikes but they are so easy

werd, im not even gonna fuck with mine, im taking it to my boy peter at HAP.
i dont have a the tools, nor do i have any experiance with the timing of anything except a clock

How much is ur boy goin to charge you to do it.

Ok, please don't tell me that in order to replace it, you have to mess with the timing??!! That is always a scary thought for me... I checked out rockauto.com and they had cheapest for $111. Thanks for the info.

the post is talking about changing the timming belt along with the sensor... the belt should be changed around 110,000 miles

i thought the belt was to be changed at 60k, and timing chains were good for 100k
someone correct me if im wrong but im pretty sure timing belt are supposed to be replaced ta 60k

the manual says like 105k for the belt. but by then i would think of it as a time bomb... im doin mine about 90k. chains are pretty much never changed unless you have like 250k+ and the timing shouldnt be too hard just read the service manual and learn where tdc is

so can anyone tell me if the vg33 is an intereference motor?

by that what do you mean ricer????

valves and pistons touch.
and i just found out from a mechanic buddy of mine that the vg is in fact and interference motor, shich means if your timing belt goes out yo shit is fucked like a chicken

I guess I had better have them do the belt too while I'm at it then, she is up to 86k. That is good to know, have it done before it goes.

its not too much more work.... well its not that bad to begin with, take out the radiator, fan, water pump, a few hoes and bam

i need to take out my radiator anyway to clean it. i dont like the super huge ac condensor that totally convers the radiator making it impossible to clean without removing

i read up on the timing belt recommended mileage
theres alot of things i do that say the 105k will be less because of.
so, im at 63k now, doing it at 85-90k

I have been told to replace the Knock Sensor too. If I look in the Haynes Manual.. . . it tell me that it is below the intake manifold on the side of the engine. . .and there is a photo too. As I look at the engine. . .I don't see it....If any one has a 2000 4cy Xterra, could you tell me EXACTLY where it is?

This may help some of you. Please note if you have a SC it is not for you.

http://www.nissanoffroad.net/messageboard/index.php?topic=1921.0

The K-sensor is just under the plenum- pretty simple. Make sure to get the pigtail harness, thats why most of them short. It wont flash a light (MIL) but it can retard the timing.

I just did the knock sensor in my 03 SC x... it took me 2 days all in all it wasn't too bad.. it did make a world of difference (better mileage and brought the power back.)

My knock sensor just went bad on my 01 SE with 90k. All the quotes I got were 4 1/2 hours of labor minimun. $ 540 was the cheapest because the have to take off the upper intake manifold and replace a gasket. Needs to be done by a certified tech. Too risky for a do-it-yourself. Tools need are fairly extensive and I have turned a Bronco II into a war wagon. Carbs easy, this projest is no fun...

I didn't replace the KS like I should have when I had a head off to replace the gasket. It's the same as any other engine, take your time and pay attention, no certification needed. No special tools needed either. The worst part is getting to the hose connections at the back of the upper intake.

I just had my timing belt done and i'm getting a hesitation at idle. The cel also flashed on and off for a few seconds when it was warming up today. My belt was pretty stretched (about an inch longer than the new one). The timing is set right according to my manual and it runs smooth on the highway. I also had the water pump changed. Do I need to change the knock sensor as well? Is this why it is idling rough?

I just had my timing belt done and i'm getting a hesitation at idle. The cel also flashed on and off for a few seconds when it was warming up today. My belt was pretty stretched (about an inch longer than the new one). The timing is set right according to my manual and it runs smooth on the highway. I also had the water pump changed. Do I need to change the knock sensor as well? Is this why it is idling rough?

The knock sensor only affects the timing advance. Every trip it resets too. Therefore it won't be the KS affecting the idle. I hope you didn't do what I did....I aligned my timing marks better than the factory when I replaced my timing belt resulting in the driverside cam being one tooth out. It also ran fine but wasn't right at idle. Reseting it back to how it was prior to the belt change fixed it.

I cant very well reset it back to where it was originally because the belt had jumped. the passenger side cam was out 1/2 a turn. I waas told you cant bend valves in these engines. Is this true???

I believe it's 105k for the timing belt,
at least that is what the dealer told me
I am replacing mine this weekend..
:pfeilimkopf-big:

I ran for several years with a bad knock sensor with no ill effects in power or fuel economy as far as I could tell. It's critical if you have SC Xterra. It is a fairly big job to change it in that you have to pull both intakes. Not worth it IMHO unless as I said you are running a SC Xterra. Also, that it will take most do it yourselfers maybe 10 hours or so, and I figure the new one will go bad again, why bother. Just my opinion though.

I just replaced the K sensor on my '02' V6 ( no SC). Normally would not do this (this was first time I performed surgery on my truck) but it was EATING gas when the SES light was on. I mean < 10 MPG!! Took it to dealer (stupid me) and they made me pay $95 for 5 min of work to tell me there was a KS and OS code... (found out later the OBD II reader costs about $100.. I have my own now). plus they wanted $1600 to do it plus various other 105K mile fixes ( fuel filter, plugs, etc) for a grand total of $2500. I told them to pound sand and picked my truck up.
I got a Nissan X repair manual on CD( it is awesome) and better than the Haynes one I bought.
Still, would not have been that bad if the shop before me hadn't stripped out the 5 bolts holding the upper Intake manifold on. I drilled them out and then had to drill out stripped fuel rail bolt as well...Grrr. Then had to wait week to order the new bolts from dealer ( @ $5 per !!). But I had pre-ordered all other parts gaskets etc. (Got my KS sensor online for $87 and OS for $60. They are Bosch parts....)
But once all parts were in I got it all back together quickly but it would not start!! after some troubleshooting found out that I had bent pins in both of the main wiring connectors that go to the fuel injectors( located on top of left valve cover). Unlike the other connectors which have really beefy pins .. these both have 8 really tiny delicate pins... if one is slightly off when you try to insert the other in... smush. So I straightened it out and it started no problem.
The job really isn't that bad. Only off tools needed are Torque Wrench, Ox sensor socket, some hose clamps and 6 mm hex key socket to remove the bolts. (That was hard to find). The rest was doable with standard metric socket set, plain tools and plenty of extensions.
Only problem is that now she runs at very high Idle. 1500 + in park and is always pulling to go... Will need to tackle that next... heard something about an IACV adjustment screw. Here goes again.....but no ECM codes any more!!

I just replaced the K sensor on my '02' V6 ( no SC). Normally would not do this (this was first time I performed surgery on my truck) but it was EATING gas when the SES light was on. I mean < 10 MPG!! Took it to dealer (stupid me) and they made me pay $95 for 5 min of work to tell me there was a KS and OS code... (found out later the OBD II reader costs about $100.. I have my own now). plus they wanted $1600 to do it plus various other 105K mile fixes ( fuel filter, plugs, etc) for a grand total of $2500. I told them to pound sand and picked my truck up.
I got a Nissan X repair manual on CD( it is awesome) and better than the Haynes one I bought.
Still, would not have been that bad if the shop before me hadn't stripped out the 5 bolts holding the upper Intake manifold on. I drilled them out and then had to drill out stripped fuel rail bolt as well...Grrr. Then had to wait week to order the new bolts from dealer ( @ $5 per !!). But I had pre-ordered all other parts gaskets etc. (Got my KS sensor online for $87 and OS for $60. They are Bosch parts....)
But once all parts were in I got it all back together quickly but it would not start!! after some troubleshooting found out that I had bent pins in both of the main wiring connectors that go to the fuel injectors( located on top of left valve cover). Unlike the other connectors which have really beefy pins .. these both have 8 really tiny delicate pins... if one is slightly off when you try to insert the other in... smush. So I straightened it out and it started no problem.
The job really isn't that bad. Only off tools needed are Torque Wrench, Ox sensor socket, some hose clamps and 6 mm hex key socket to remove the bolts. (That was hard to find). The rest was doable with standard metric socket set, plain tools and plenty of extensions.
Only problem is that now she runs at very high Idle. 1500 + in park and is always pulling to go... Will need to tackle that next... heard something about an IACV adjustment screw. Here goes again.....but no ECM codes any more!!

The KS doesn't cause the CEL that would have been the O2 sensor (which would have also caused the bad mpg).

I'm suspecting you have a manifold or vacuum leak causing the high idle.

I agree with k1w1t1m about your high idle. Sounds as if you have a good vacuum leak somewhere. Just take some either(starting fluid) and spray in different areas around the intake manifold. When you hear the motor rev up you've narrowed down the search. Good luck.

Check you owners manual, my xterra manual says change the belt at 105,000 but honestly if you do a lot of rough driving, I would probably do it around 90,000. Also, I just got a quote for my Honda Civic and the dealership wanted $780 to replace it. I called some local shops and got quoted around $450-$600. I was supposed to change my timing belt at 100,000 miles, my civic has 158,000 miles on it and the sucker has not broke yet. I am taking it in this weekend to get it done finally, I lucked out that it did not snap. It has a interference engine which would have crushed my valves if the belt broke. Honda's and Nissan's man, those cars run forever.