I have two fouth Gen Maximas, a 96 and a 99. They are both GLEs. My wife's 99 is very noticably slower. Even she notices a big difference - she fries the tires in my car after driving hers because she has to stand on hers to get performance. My car seems light, nimble and fast - her car drives like a boat.

I have a K&N filter on hers no mods at all to my car, that I know of. I bought them both used. Is there something that I can do to hers that will get it to perform closer to mine and that won't be expensive?

her knock sensor is probably bad

yea, that would be my guess also. how many miles?

well the '99 maximas r much heavier than the 96's because they had much more parts because of emissions

"won't be expensive" How about money back!....... Sell the 99 and buy a 96! LOL
Your info is a little vague, there could be so many factors that stops a definitive answer, try starting with a complete tuneup, plugs, oil, throttle body clean. Is there much of an odometer difference?

Could be the KS as suggested. Check the codes as it won't set off the CEL.

95-96 are lighter, but it shouldn't be noticeable.

Is her's cali-spec? I believe they have an extra precat and since elimination of the precats is what gives aftermarket y-pipes their gain it would make sense that an extra one would further reduce performance.

Since her's is a 99 the coil packs could have gone bad. I would think that would set off the CEL, but I don't really know.

The heaviness factor is true, but I don't know about all this knock sensor talk...

If the check engine light isn't on then it probably isn't your knock sensor, people just like to pin it on poor performance because it's an all-too-easy diagnosis for a power loss situation.

Thats not true, a bad knock sensor WILL NOT trip the CEL light, you have to run the codes yourself to see if the knock has gone bad.

prolly the knock sensor

eh you are wrong. as said above the knock sensor doesnt trip a CEL. its a ghost code. dont give misinformation.

knock sensor failure is the most common cause of performance loss. check for codes, then go from there.

And thank you for backing me up.

Besure to check out your information before giving it out;

- Bad knock sensor info.
- 95-96 Red Clear info.
- So so so much more of the recent questions and advice given on the Org.

Don'tn forget the coils

I didn't .

The KS is often suggested because it is often goes bad (especially as our beloved 4th gens grow older) and unless you check the codes for no reason (since there's no CEL) then you won't know about it. It really does make a big difference too.

No, THATS not true, my knock sensor went bad a while ago, and guess what, it threw a code.

Be sure to check out your information before giving it out

98 SE w/only 65k miles. No CEL. BIG difference in performance.

throwing a code, doesnt mean it trips the CEL!!!!!!

Ummm...it throws a code but the Check Engine Light won't come on. They're right.

Oh, yeah, sorry guys, it tripped the CEL, and also threw a code (duh), my fault.

So, in conclusion, a bad knock sensor did trip the CEL, at least in my car. I don't know how you can argue that...

It really doesn't matter, but you did say:

But you are correct. There will be a code, but not a light (unless something else is wrong).

wats a good price for a new ks?? my car has 138000 miles

$90 shipped on ebay. $112 plus shipping from Jr nissan with "maxima" promo code. Don't just replace it though. Check your codes.

Just follow me for a second, we are arguing that a bad knock sensor (with the exception of your Maxima and a mabye a couple others) will not trip a CEL light and will throw a code. Our point is that you said "because your CEL is not on it is probably not your knock sensor" when in truth if the CEL is not on and there is a big loss in power chances are with that year and mileage it is probably the knock sensor...........now let this one go and move on with your life.

- Steve

KS dont trip CEL's... ok?

You should be banned forever for stupidity.

I have a 95 and a 96 SE. How do I go about checking codes on these to see if either of them has a bad KS? My 95 has 206k and I'm concerned about it's performance. Thanks.

daveyg68

This guy wanted to know why his wifes car lacked to his. And you gave him an arguement over whether or not the CEL is triggered. WOW, I love the .org
Welcome to it man Where question are asked and off topic arguments are started.
BTW, it is true, your information is vague. A master mechanic couldnt even figure this one out without more information.

Do a tuneup on the 99 (or both if you want to - not that expensive if you use NGK copper plugs). If the 99 runs like crap performance wise then I'm guessing it's the coil packs or knock sensor.

Have the 99's computer checked for codes at AutoZone for free. Since you do have a 96, take your coil packs (less problematic than the 99s) and put them in the 99 to see if that helps.

Mostly likely giving the cars a tuneup and checking the coil pack problem on the 99 will fix it. Also clean the throttle body on each car and use some Sea Foam to help get some of the carbon out (check the Fluids & Lub section of the forums)

Let's just say, "no."

Thanks folks for all of the input. I never expected as much. You all were great. Sorry to create a stir though. To answer some of your questions... I don't have any CE lights on and the mileage diff is... my car has 128K my wife's about 90K. They have been this way since I bought them both at about 80K. I have not done tune-ups on either car though it sounds like the first thing I should do. I will also look into the KS since it sounds like a reasonably easy thing to get checked. Thanks a lot.

It sounds like your in the right track. After I tuned up mine mine felt a lot better. So much so I wish I would have brought it to the track. Performance has slipped a little now, I think I need some plugs.

Can let us know what you find out?

Good Luck,
Gears

What about a fuel injector cleaning. Do those help?

True. Two summers ago my knock sensor went bad (about 160k miles or so) and I found out because the CEL came on. Why would the ECU trip an error code and not alert the driver?

what...a knock sensor will throw a code, no one said it wouldn't. they just said it wouldn't trip the CEL, which is correct.

The knock sensor code can come up for several different reasons including but not limited to:

O2 sensor malfunction
Knock sensor malfuntion
Knock sensor detecting knocking/pinging

Now can you imagine the CEL coming on every single time your engine knocked or pinged??....that's why...

[QUOTE=DAVE Sz]You should be banned forever for stupidity.

why is that

prove me wrong

weight diff from a 96 and a 99 is like under 70 lbs. heavier front impact bumper reinforcement, a little bit of emmision stuff. doesnt make much of a difference at all.

tune up the cars first. then let us know if there is still a problem. most likely just bad plugs, coils, dirty air filter, possibly bad KS. theres a bunch of things.

Weight difference between a 96 and a 99 isn't more than 15lbs, maybe even 10.

Do you know that for sure or are you speculating like he was??