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Maybe power...little if any. Too early to tell on the mileage....but it had an annoying rough idle I just could not figure out... This appears to have fixed it. I had reset the timing about a month ago so I may need to do that again now that the truck thinks it is running correctly.
 

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Might be giving this one a shot soon throwing a code for a KS in addition to some other problems. Hopefully this takes care of a few of my issues.
 

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Might be giving this one a shot soon throwing a code for a KS in addition to some other problems. Hopefully this takes care of a few of my issues.
It won't unfortunately.
 

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I just installed my variation of this mod. I used a mini mag solitaire case to hold the resistors and got the sensor side male connectors to use for the wires. no soldering to the factory wires (old sensor wires now wrapped in tape ) and "new" ones have factory waterproofing plugs



hope this link works . it shows the completed "resist-a-knock-off" installed
I used this as I wanted to set it and forget it. protection of the resistor pack while using the factory wiring .. :)
 

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I just purchased 10 560k ohm resistors. Just to clarify , 560 ohm and 560k ohm resitors are different hence the 560K . Radio shack does NOT carry these resistors even in their book. If anyone needs a resistor, PM me your address and Ill gladly mail one out to you free of charge!!
 

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Right. Radio Shack carries 470K + 100K resistors. Works just fine. Generous of you to offer still!
 

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I wound up picking up a variety pack of resistors to have a chance to prototype the setup I was also concerned about the heat generated across each of the resistors. (get the 1/2 watt) My engineer brother said not to worry about the heat. 2.4 volts across 470k ohms = not much btu. I wound up using two 270k and one 22k . so far the XT loves it, better pickup/idling. much easier than pulling the manifolds :)
 

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OK This modification is a piece of cake with a single 560K resistor. The Cream and Gray wire I snipped on the knock sensor side of the plug, soldered the resistor to the gray and then to the cream wire and stuffed in the stock loom and electrical taped the loom. Looks stock. All in all took me 10 minutes . Mine is a N/A Xterra with the 8 pin connector. I felt snipping the wires on the knock sensor side of the plug was better than removing pins out of the factory plug not only because its much simpler, but keep the plug and engine harness in tact and undisturbed. Cleared original Knock sensor codes out, checked base timing and drove it this morning.

Power has been restored, MUCH smoother on an already smooth engine, not running near as rich and no codes have reappeared!!
 

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ok, fellow Xterrans,
I installed the knock sensor resistor mod and noticed a marked increase in performance. I used my code reader to view live data and noticed the timing advance was now 25 degrees advanced(prior to mod it was around 12/15 degrees) so there is a clear downgrade if the knock sensor is not working.

is 25 degree advance "normal" or should I find a timing light and reset it ?

Thanks!
John
 

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ok thanks for that link .. i unplugged the tps and the timing goes to 10 degrees on the obd live data...looks to be spot on !
 

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No it is even better on non-SC ones, because on the SC ones the knock sensor is pretty important and bypassing it is risky with boost. You dont really have to worry about detonation as much with a non-SC and thus bypassing the sensor is not as big a deal, and will help solve a lot of problems as a result of the truck automatically changing the timing and such to compensate for a bad sensor.
 

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yeah thats right .. when the x sees the bad sensor it retards the spark to avoid the knocks. if we replace it with a resistor mod, the ecm then thinks the knock sensor is performing well and advances the timing accordingly. if you do the mod , you ought to pay attention to bad gas ,good tuning, and those long slow hills that tend to invoke the rattles.. I know my performance with my 2004 vg33 XT improved after installed the resistor mod.I think its much better than pulling the intake off and replacing the knock sensor that likely to go bad within a year ....the service manual admonishes you to not use a sensor that been dropped or mishandled...sensitive little buggers...
 

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Wow. I did this mod today on my 2002 xterra with 3.3 v6 n/a . My gas mileage and power have been dropping. I use to get 260+ per tank and I have been getting 200 or less per tank. NOTICEABLE difference as soon as I took it for a test drive. Soon to see on gas mileage.
 

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I am still getting 300 miles / tank here (20 miles highway each way to work). We used to fill up at 200. My gas light has never worked so we go by mileage. I dont trust the gauge. it seems to stop at like 1/10 tank no matter what.
 

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how long ago did you do the by pass on the knock sensor and have you noticed any difference in your performance? fuel mileage? Have you had any problems since the bypass or caused by the bypass??

Thanks much,
Jim
 

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I got a pack of 560k ohm resistors from frys for $2. They are only 1/4watt but have worked so far. FYI in the 2000 manual it says a value from 500K-620K ohm is acceptable when testing for a bad knock sensor. Pretty sure thats where the 560k is coming from since its the middle.
Some people have been concerned that after doing the resistor, the knock sensor signal will be constant, so timing could be too advanced at times. I know that's not the only thing that affects timing however, but would it be a good idea to use a resistor more towards the end of that 500K-620 kohm scale that would retard the timing a bit, instead of one in the center? Or does it not chance at all in that range?
 
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