nadir_s

first of all, i apoligize for asking a question regarding knock sensors ... i know they come up about every other thread lol, but had to get this out there for my satisfaction.


I read Steve's summary on knock sensors in the FAQs...

so basically, if I were to bypass the KS by putting in a 470k resistor, the car would run as if I had a PERFECT knock sensor, right?

I want to see if there's any difference in performance. I can't really say the car is sluggish (5-spd), but if I found a difference or increase in performance, at least I'll know i should replace the knock sensor. The car is nearing 200k miles and i've never had to replace the KS.


I am glad with such an old engine, idling is smooth. However, when I go WOT, the car feels hesistant. It's not a consistant/smooth acceleration... somethin u just feel. I have a brand new 300Z fuel filter that i installed a couple months ago ... didn't help. I installed new NGK plat sparkplugs about 15k miles ago too.

edit: btw, gas mileage is OK: 360-400 mi. a tank (80-90% highway)


thanks

knight71

Yes, you're right. installing the resistor would be the same thing as installing a brand new knock sensor, therfore you're performance will increase, since your car thinks you've installed a new KS. However, doing this, is risky., just order a brand new
KS from www.jerryromenissan.com. Its only $90, and it easy to install. You have a nice car, why take that risk?

mzmtg

iTrader: (11)

Installing the resistor would make your car run maximum timing advance.

But, if the engine is actually knocking (yes it happens before you can hear it), the ECU won't know it and wont retard timing. This is bad for power and bad for your engine...potentially.

joecraps

I had the resistor in for about a month and just installed a new KS and harness. One thing I noticed with the resistor was that at start-up the engine seemed too advanced - frequently the engine would roll over and catch so quickly the the starter gear didn't have time to disengage. The starter is fairly new BTW. Needles to say, I didn't like the idea of having my starter gear or flywheel gear teeth getting ground up into dust - this on top of having to be a "human KS" - constantly listning for knock noise. Didn't matter if the engine was cold or hot. With the new KS installed startups are smooth and the car seems just as strong on the road. My take, buy a KS and forget the resistor - the risk just isn't worth the money saved. The KS is there for a reason.

As for your milage - 360 to 400 seems a little low for 80-90% highway - check your ecu codes. Also, change your fuel filter if it hasn't been done recently.

nadir_s

hmmmm thanks guys. I think ill just look for a code (haven't even done that EVER). Actually, i'm sorta hoping it's a bad KS ... there's definately some sort of hesitation goin on.

car takes forever to start sometimes too. I was beginning to think it as the starter because I had my brother change a starter in his 97 maxima and he told me that the car started up almost instantly.

joecraps

Yeah, I'm on my third starter on my Max - got a Bosch recently and it looked to be better constructed. The OEM gave out around 90K miles, the second was some remanufactured crap from Autozone and lasted bout 30K.

nadir_s

o crap - put in a reman starter from autozone for my brother ... but it has lifetime warranty

nadir_s

another question -


does a bad knock sensor contribute to failing emission levels? So far, i've been able to pass, but last year i passed just barely.

Mishmosh

iTrader: (3)

I got a reman starter from autozone after my OEM one started making noises (ie. needed regreasing). The reman definitely starts up with less gusto! WTF!

the KS can give you worse emissions testing by making you run richer than before.

nadir_s

ok i took a voltmeter to see what the resistance was ...

i located the knock sensor (pretty easy to find and looks really easy to remove too ... ) then i followed the wires to a connector. The wires were solid black and a transparent gold (almost like speaker wire).

Anyways, I removed the connector that was connected to it and saw 2 long pins. I did not see a difference in height however. ..

so i know these two pins have to be connected to the knock sensor though ... no other wires tracing to it. Anyways, I took my voltmeter and i tested BOTH pins (kept one probe on the voltmeter at the battery negative terminal) and the other to one or the other pin.

I didn't get any reading at all .. i know my voltmeter is capable of both M and k ohms.



do u think im doin something wrong or is my knock sensor fried? i hope i didn't have to turn on the car or something ... altho i don't see any difference it would make considering the knock sensor would be totally disconnected.



i guess my next bet is to check the ECU for codes?

nadir_s

ahh ok

i checked the ECU for the first time ever .... click click click ---- click click click click

bad knock sensor

yay now i get more power

Mishmosh

iTrader: (3)

Just FYI, the black lead of the harness is blind-ended. The KS itself is grounded through it's body. When testing, you should either have the KS removed and directly measure resistance across it's terminals OR use the harness and measure the difference from the hot lead to chassis/battery ground.

Yeah, the KS does make a good 15% or so more power. Your average joe may not appreciate it but certainly Org members will. Just remember to reset/clear your ECU after you replace it.

nadir_s

thanks alot


yeah , i didn't remove the knock sensor itself and test the leads directly on it ... jsut traced the wires and did it at the subharness connector.

oh well, i figured my knock sensor didn't survive after 180k miles ... i'm wondering if I had this car for the past 3 years with a bad knock sensor ... i hope i did!

guess it's time to take a look at jerryromenissan.com

Mishmosh

iTrader: (3)

not sure, but I read in a different thread that JRNissan no longer accepts org discount code. Maybe you can look into that...

nadir_s

you're right ...

pinnaclenissan sells em 79 shipped!

Mishmosh

iTrader: (3)

Geez! Unbelievable deal! How'd you hear about that and does pinnacle sell other parts at discount?

nadir_s

it came up in another thread recently related to knock sensors ....

so i can either buy a brand new OEM knock sensor on ebay for 89+shipped = $100

OR

generic (probably BOSCH) knock sensor at pinnacle for 79+freeshipping= $79


hmmmm what to do! i've read every single thread on the ORG related to the bosch KS and it is virtually identical to the OEM one (marking, size, etc.) .. which concludes that OEM is bosche...

damnit decisions decisions ... what would you do? fork uip the extra 20 for a bosche? damnit apparently thepartsbin.com had the bosche for like 30 bucks just recently on sale ...

what to do!

OEM or bosch?

Mishmosh

iTrader: (3)

I would just get the Bosch. More than likely, it actually is OEM. I know the O2 sensors was the same deal also (ordered from thepartsbin--thumbs up). Either way, no doubt the last KS you will buy for your max...

VQuick

iTrader: (17)

So Nadir, did you decide on the generic from Pinnacle and did it turn out to be Bosch?

nadir_s

well, i called up pinnacle again before I had ordered it and the guy i spoke to claims they only sell OEM ... so i'm not sure if it's OEM or "generic".

I will find out tomorrow (monday) .. that's when the sensor will be at my door.

I'll take a couple of pics and post it for you.

I'll also take picture comparison between the original sensor that comes out of my car and the new one.

nadir_s

alright so i got my package today.

the sensor is brand new and it's a generic box, however there's a sticker on it that says:

part# 2206030P00
SENSOR KNOCK
MADE IN JAPAN


and on the sensor itself, it says 5321 UNISIA JECS JAPAN *nissan emblem* A53-600 M01


ah well, this is as good as it's going to get for me lol.

don't see anything about Bosche on it though.

1chewabacha1

iTrader: (6)

Okay, I read the DIY's but I still can't take out my dam KS!!!!! my hands can't reach down there! Is there a special tool that you guys use to take it out? How would you torque it down?

Loe max

iTrader: (6)

Yep, thats the OEM one. Was yours cracked like mine?

nismos14

iTrader: (56)

so did you get some performance back?

nadir_s

dunno yet guys, trying to take it off as we speak lol

i have a breaker bar, but my 1/2" adapter -> 3/8" adapter -> 12mm socket is a bit too tall ...

gonna see if i can just get a 12mm socket that fits a 1/2" socket wrench/breaker bar.


OR just gonna see if i can get a 3/8" swivel joint (i got one for a 1/2" but no extensions or sockets for it )... i got a billion extensions lying around.

ill post results in a half hour

nismos14

iTrader: (56)

cool beans have fun

nadir_s

holy ****ing ****

i spent $10 on this u-joint and for some reason, there's just that little bit of play that won't "lock" on to turn the bolt.

i am so pissed, and what the **** is that sensor thing right in front of the opening. I want to remove that because it's poking into my hand.

argh so frustrating ... so the swivel bolt thing is completely useless at this point.

I'm thinkin i need to go back and buy a very long 12" wrench to see if that does the trick.


edit: **** , i didn't know how a swivel 12" socket lookd like ... i got the 3/8" swivel instead.... gonna go back that and get it

InsneDrmr

iTrader: (1)

when i tested my knock sensor, i just used the multimeter on the leads inside the harness. I didnt touch the battery. Should I have done that?

nadir_s

OK

didn't get it off tonite ....

just gonna go to sears and get the right 12" swivel and ****.

4x4Max

iTrader: (12)

sounds pretty hard to take it off...i have monster hands too, so how much would it cost to have the dealer change it?

nadir_s

u can still do it yourself

i am able to get my hands in there too.


i'm going out right now to try again .. probably will remove the sensor right in front of the opening. this way, i'll be able to get my long wrench in there easily and try to turn.

i did spray some penetrating oil yesterday in hopes to loosen it.

nadir_s

WOOT

ok i got it done.

i wasn't able to fit my torque wrench in there so I just hand-tightened it.

i reset the code .... time to go to school and "test" it.

i have alot of pics of comparison and stuff that will help some ppl out who haven't tried this before. .. i ll make a new thread and post a link to it here in the evening.

woooooooooooooot!

nadir_s

here are my results and conclusions .. with pics too


http://forums.maxima.org/showthread.php?t=402982