Code for both comes and goes, guessing mostly because of the O2 sensor causing the knock to occur. I was going to get the O2 sensor done first, but I was curious on what a good price was, being quoted $350 or so for the part and replacement.

BTW, I am back from a long hiatus, this is our "4th" 4th Gen (99 Crimson Blaze SE-L 5 speed).

Thanks in advance for responses. I just had the oil pressure sending unit replaced, the cps seal, all the belts and an alignment, all for $347. Figured the shop was giving me a fair price on the O2 sensor replacement quote, but wanted to get some experienced estimates.

If your going to get o2 sensor go with denso look on amazon i think i paid 40.00 dollars for it mine was the one after the cat which was plug and play ...as far as the knock sensor some times it will trigger it ,so get the o2 done first ... You can tell if the knock sensor is bad by looking under the hood were it sits with a flash-lite check for cracks around the base if so replace...

Ebay KS works fine, so around $15 on it.


Posted from Maxima.org App for Android

Its not hard to replace either of those. If you can't do it yourself, i wouldn't pay over $200 on labor, because the KS takes about 30-45 minutes, and the O2 would take around the same if it's not rusted to the pipe, and depending on which O2 sensor it is. Shops usually charge $100 an hour for labor, so you can go by that and see the price they gave isnt astronomical, but it isnt necessarily good, either.


Posted from Maxima.org App for Android

$350 for an o2 and ks! Wow, Im currently shopping around for the same and would never pay that. I assume thatt price includes installation. Do yourself a favor find a good online source, like rockauto.com, do a bit of searching here for how to change out these two sensors. You will quickly realize that you are being taken for a ride down the "let's see how much we can milk for this simple job" train. IMHO, Roll your sleeves up and get a little dirty to save yourself at least $150 if not more. Most of that quote is in labour and Nissan's unreasonable price of apx. $120 for a ks. E-bay has knock sensors for $15 and up. Just make sure you buy yours from someone with a good seller rating.

Thanks for the replies. I have tried to change a knock sensor years ago, but my fat hands wouldn't fit, unless I just removed the intake manifold. I'm thinking that may be a little beyond my training. I will look up the O2 sensor online and see if that fixes the problem. The light goes off, unless the car hiccups at very low rpms, under load, so I am thinking it's just the O2, I hope.

The OP has a 99 Maxima. More than likely it's a CA spec Max. You guys need to realize that a KS can't be changed easily in 30 minutes on a CA spec Max...it just can't. A bunch of swirl valve related crap, unique to CA spec 99's, is in the way. The UIM has to be removed at a minimum. Until someone shows a video on a 99 CA spec with some special tools, I'm gonna call BS.

Or a small fault in a coil pack at that running condition. How old are your coils?

Was thinking it was normal fed spec. So no BS on a fed spec. Op says the only problem is chubby hands. If the car is a fed spec then he just needs to borrow a smaller set of hands. Thanks for pointing that out though because its very true on a Cali spec.

Op: is you Max fed or Cali spec?

My hands aren't technically "fat" (I weigh 160 lbs) but they are big. I checked under the hood, and it says "usepa specs" so I assume it's a federal spec not ca spec. Funny someone should mention the coil pack issue, after I posted that, one of my coil packs decided to fail. I replaced it with a used coil pack (with the help of the previous owner). The previous owner had given me an entire set of new ones he had put in, then took back off after they threw a CEL. He had also thrown in a couple of used ones he picked up so he could pass emissions here in GA. After checking the price of new OEM's, I'm thinking I am getting a meter and checking used coil packs at the pull a part!

Sorry didn't mean to imply anything there is a lot of people who can't fit their hands in there.
So are you just planning to buy coils for future use? Or is there still a performance problem going on?

Well, number 6 completely failed, so I pulled it and replaced it with a used coil pack. Still have that little hiccup at low rpms (sometimes) but at least all 6 are firing now. After researching the coil packs (I have 6 brand new aftermarket ones) I am nervous about using the new ones I have, as the previous owner said they threw a code, so he just started using used coil packs. I can't run out and buy 6 new OEM packs though...bit over budget. I will probably just replace the O2 sensor, and go from there.

On a side note, it appears I have a rare car (SE-L crimson blaze 5 speed, with us epa specs), kind of happy about that.

To me personally thats pretty much the best 4th gen there is.

As for the knock sensor i succeeded using very long extenions with a swivel head at the end to take the ks off. I was also using an extendable magnet stick to kind of guide the socket where it had to go.

As for getting the new sensor in and bolted down, boy what a tedious pain. The same setup with a little bit of masking tape to hold the bolt worked but holy crap that bolt did not want to line up.

BTW this was on a CA spec, so im sure you could have the same success much easier as i could only get under there from an extremely limited angle.

Thanks, I'll keep this post in mind. Today, no CEL light, everything seems ok, except for the occasional low rpm acceleration hiccup. I'll change the O2 sensor first and see what happens.

Understandable coil packs are not cheap and you

Understandable. coil packs are not cheap and the cheap ones have the wrong resistance and will throw codes, ( from what I'be been told).

Nice, very nice!

saw the author of this thread and thought for sure it was a resurrected thread from like 2003...

welcome back veetec.

Thanks, glad to be back!

Just an update, CEL went off and runs fine since replacing one coil pack. When I say fine, I mean best 4th gen. we have owned in smoothness and likely power! Hard to believe it has so many miles..this car was seriously taken care of.

Here's on my 3rd DSC4.

I currently have a 99 Max 5-speed and a 99 I30 automatic. I like to buy used DSC4's with about 150,000 miles (half life) where the previous owner is ready to jump due to a combination of CEL codes. One thing I've noticed about our cars in all cases when I buy one the O2 sensors are randomly throwing codes in addition to a KS code.

Since I can tell the the O2 sensors are usually original equipment by the cable covering, I start planning to replace them ALL with NGK/NTK sensors that I get at a good price from www.rockauto.com. I've read and experienced where O2 sensors start to get lazy after 100,000 miles. After changing O2 sensors, I notice better MPG (~2) and better low end performance around town. Also for the 5-speed DSC4, there is a low end bucking in 1st gear that goes away after replacing O2 sensors. I have an older V8 Infiniti with the VQ45DE that uses OBD1 instead of ODB2. For that ODB1 setup, it is recommended to change the both O2 sensors every 60,000 miles.

For the random KS code, I've noticed after I replace the O2 sensors and start using premium fuel, the KS code will go away. Eventually I will replace the KS as part of a general service where I remove the plenum to replace our beloved valve cover gaskets.

The good news is O2 sensors for our DSC4s are not as expensive as some other Japanese brands. I recently had to spend about $360 (my discounted cost) for me to DIY replace all 4 O2 sensors on a V6 Honda at 120,000 miles. Ouch! That one started drinking gas like crazy and became sluggish -- even after new NGK plugs. It never threw a CEL code. New O2 sensors brought back in town performance and restored original MPG.

For what it is worth, just search on "Lazy O2 Sensors" as there is plenty of information around about returning optimal performance to a car with over 100,000 miles by refreshing the O2 sensors.