I have a cali-spec 99 max, so from what I've heard, it'll be even harder to replace my knock sensor. I already bought a new one, I just need to put it in somehow.

My mechanic said that 99% of the time, when the KS light comes on on nissan's, it really doesn't need to be replaced. They are just very sensitive. Unless I can notice something wrong with my car, I don't need to replace it.

Is he somewhat true on this? From what I've gathered on the forum, it seems like a pretty essential replacement when it goes bad. So he didn't really seem too eager about replacing it.. is there a lot of work involved in removing the manifold (of course he said this needs to be done to replace)? Either he's too lazy to dig in and replace it, or he's just trying to save me some money.. but I already bought the KS.

Thanks,
Dan

 

1. the KS won't set the CEL - so if your CEL is lit, you have at least one or more other codes in there.
2. it is common to get the KS code with other codes - in this case, fix all the other codes first, reset the ECU and check again for codes in a week or so (even if the CEL is off). If the KS code appears ON IT'S OWN, then you have a bad KS or connection to the KS and it needs attention.

 

I haven't had a CEL light for at least several months, I just checked codes last week at Auto Zone and the KS ghost code came up. As expected. Because a few months ago, I was getting a separate problem fixed which triggered the CEL light, and my mechanic let me know then that the KS code came up.

 

Then you need to address that knock sensor code. Check the harness, grounds and the KS itself...

 

I had no CES codes showing when I replaced my KS (@70k) but after I replaced it, I noticed a significant improvement in initial acceleration.

 

they probably need to be replaced because you put in to low of an octain gas because you think prices are too steep?

mabe mabe not. thats just my take on the issue, im guessing thats not true, but i dont know u or your car.

and like someone said above, their mabe more than just that one code, so see what that is too.

 

Octane

there, their, they're

KS doesn't go out because of the grade of fuel used.

 

Only the best for my baby... I have only put in Super at the pump. Sorry to kill your theory!

 

Not trying to be rude, but your mechanic seems lazy or doesn't want to tackle the job because it is a little hard.
From what you have told us you checked on numerous occasions and have gotten the KS code. Based on that it needs to be replaced.

Im not sure where he got 99% of the time either. Im not saying a bad ground or something else wont trigger it but he has some interesting stats.

You already have the KS just find someone to put it in.
I had my KS replaced for $60 and they didnt have to take off the manifold, but i have a 98. I dont know what the difference is for the 99's if there is any
( i remeber reading about some kind of swirl valve for 99's)

 

I actually went to Nissan and they basically told me the same thing. I just wanted the part and the guy in the parts department was just like even if the code is there don't replace it because it's not doing anything and there may not be a problem with it. He rambled on about some other things but I didn't really pay attention. I ended up buying one off ebay.

 

Yes, yes, and yes. speaka da engls wen postng

 

I replaced mine anyways too. Wtf. Why do nissan mechanics know nothing??

 

Did you guys notice any improvements in driving after replacement?

I think I'm going to want to replace it either way, so I can have some peace of mind. 150,000 is a lot of miles anyway. I'm gonna take one last look at my car later today, and see if I can even spot the sensor, if the job just seems too tough I'll throw in the towel and go mechanic shopping.



My local Nissan parts manager told me there was no such thing as a 99 SE-L a few months back. I was like, uh, are you sure.

 

i recommend checking for the ghost KS code first. Perform the standard ECU diagnosis and if only code 0304 comes up, replace it.

 

I got the code, twice actually. Went to Auto Zone a couple weeks ago and borrowed their OBD-II. The 0304 code came up twice. So I am fairly confident it needs replacing..

Thanks.

 

Felt better than any mod I had ever put on the car ..

 

oh ok. yea, def needs to be replaced then!

 

haha. yea, I felt a SLIGHT gain. Nothing too incredible.

Don't expect to be smoking vettes after you replace the KS.

 

UNLESS its an early 80s vette

 

...................

 

LOL. true. Those "vettes" in the early 80's didn't even deserve that name. If I recall, some were being rolled out of the GM plants with only 180hp.

 

On a 99, you have to have extremly small hands or a very flexible joint socket to get to it because the lower manifolds have a swirl-inducing butterfly flaps.

Do it yourself. Removing the upper manifold is a piece of cake.

 

I thought that was only on the cali-specs?

 

probably 99 are tEh>

 

bahleted post.

 

OMFG... you should call the manager of that dealership and tell him what's what!

I replaced the KS on my '95 SE Fed. several days ago. I needed one of those universal articulating socket thingies, a long socket extension on my little torque wrench, and light. Also had to remove one or two intake bits, but not the upper manifold. It took me some time, but it worked out just fine. Getting the new one in was the hardest part. I basically had to jam my hand in there with the new KS and then figure out how to position it with my fingers once it was all in there.

After 10 seconds of driving with the new KS, I felt like my car had come back from vacation. It was slightly quicker with the AC on than it had been with the busted KS and the AC off. With the new KS and AC off, it felt much quicker. I tend to be super picky about these things, though, so I can see how other (perhaps more normal) people wouldn't think it's a massive difference.

 

does anyone know how much it costs to get the knock sensor replaced..i live in ny and passing the inspections a real pain in the @ss..i need a new one and cant do it myself.

 

Call around and get prices....

 

There is basically no reason not to do it yourself. You pay 20 bucks for the tools and then it takes you a half hour to change it. It is basic one bolt one harness. A dealership will probably charge you to take off the IM which in the book has to be at least an hour or two then to put it back on another hour or two and you are at I dunno what the going rate is but we will be generous with 50 an hour and you are at $200. Not worth it to me.

 

Fadeaway-

Just pm'd you on how I did the KS on my 99 cali spec today. The frustration factor drove me to smoke a pack of cigs and kick my dog, but it's all done. I gave my dog some treats after too.

 

IM on a 98??
i heard theres nothing to take off..to get to the sensor..its only like that in 95-97..but im probably wrong..and my mechanic is so expensive..86.25 an hour. I can drive the car fine, but im starting to get bad mpg..its worth it to pay a little more to me, bc im not too mechanically inclined, nor do i feel like buying the tools and doing all that.

 

Need to replace the knock sensor anytime is fails. What happens is the ECU will retard the timing a bit and also run a slightly richer mixture. This means more gas spent and less performance. The reason it does this is if there is a knock sensor failure, it cannot tell if the engine is detonating or not. Therefore it runs the fuel/air map to a more conservative level.

Over a year or two you'll probably get back in gas what you spent getting a knock sensor for $99 off ebay and changing it yourself. There are tons of write-ups on here how to DIY and you don't have to disassemble any of the intake parts.

 

There is no reason you can't replace the knock sensor yourself. Hell my girlfriend could replace the knock sensor. I replaced mine in 15 minutes when I did it using nothing but your standard combination wrench and jamming my hand in there making sure it came out looking like a pile of bloody maggots lol

 

I took mine out using the uber wrench method since my hands were too big to squueze in there. You should replace it though you'll feel the difference asap.

 

i am having crazy problem trying to get that damn bolt off.....it is the orginal knock sensor car has 140,000 miles on it and i have no codes for it,but i work at autozone and got one cheap that someone did not want.....

anyone eles have a problem getting that damn bolt off?

and they do not lie about that **** having razors in there or something, i do nto even feel getting cut but i pulled my hand out with littlwe cuts everywhere acouple times.

 

If I can do it on my 99 cali spec, you can definately do it on your 97. Mind you, I did my first spark plug change last month. Before that, I was a prissy biotch and never got my hands dirty. Maybe you're having the same problem I had when I did mine a few days ago. First, I used a 1/4 inch ratchet and extention setup. Seems I couldn't apply enough torque with it. Then I moved onto a 1/2 inch setup and it broke free quite easily. The theory of "bigger is better" applyed there. Another thing I noticed was, because of the weird angle I had to go in with the extension, the U joint would lock up. So I made sure the joint has free play before I seated the socket onto the bolt. Good luck with that man.

 

i have not doubt that i can do it, but it tried for alittle while and it world nto brake loose, but i was also using some other tools, i am going to buy a joint connector and hopfully get ti with that......all i know is that it is getting done tomarrow

 

Thanks for the help guys. If I don't have my Circuit City interview tomorrow, I'm gonna get this KS crap out of the way.

BTW, if anyone wants to see the huge obstacle which is blocking the tunnel of death on 99 cali specs, feel free:
http://www.discountmags.com/maxima/

One more question-- you guys that have changed out their knocks, did you sand the connectors on the upper intake manifold like Motorvate.ca suggests?

Thanks,
Dan

 

Yea I did. I took a dremel and cleaned the contact point on the intake manifold and cleaned off the connectors too. Since I went through two hours of farken hell, figured one more step wouldn't kill me.

 

Pulling KS code 0325 for 2 years, CEL has been on for like 5 years w/ no problems. Had below work done recently...(in order)
1: Vehicle Speed Sensor
2: Speedometer
3: MAF Sensor (I did myself with aftermarket from Advanced Auto)

After changing speedometer, CEL disappeared for 1 week, then came back. Car driving ok now, but I haven't had a chance to check for any new codes...

After changing MAF sensor, reset ECU and car seems ok...

My initial problem was car hesitated and was sluggish after car got very hot... I know the 3 things above are very popular items to go in 4th Gen Maximas. I haven't had an extremely hot day since this above work was done, but a couple of days was stuck in traffic while temp was in 80s and didn't have any problems... so far so good.... but...

Any ideas what can be triping CEL ?

Thanks in advance.