# VG30 Relocate Knock Sensor?? HELP!



## dkyuss (Jun 26, 2007)

So, I had symptoms of a bad knock sensor, ECU codes confirmed it, on my 91 Maxima SE. Crawling around under the car, I was able to find the KS, get an oversized (1" I think) socket on it as the 24mm did not fit past the motor mount. Then connected to the socket with a UV joint on a ~30º angle to an extension on an impact wrench. I sat on that impact wrench for several minutes, trying to remove the knock sensor.

Yes it was in reverse.... UV joint and socket were too hot to touch when I stopped....... Did I mention 290,000 kms and I wouldn't be surprised if it is the original sensor.

So....... this brings me to my problem. As this car has many miles, I dont really want to just bypass it with a resistor and trust that high octane will always provide proper ignition (as I have seen recommended).

Could I simply relocate the sensor? Where to? This KS threads directly into the engine so I would need to drill and tap a new hole...into, but not through the engine casing.... I cannot imagine this being an easy task!

As I picture in my mind, the easiest solution would to purchase a different style knock sensor, one that is dough nut shaped and mounted through the use of a shouldered bolt. Then simply find a bolt, to replace with a longer one to accommodate the attached knock sensor and rewire it.

Does this sound plausible???? Where could I mount it to???? What locations should I look at or avoid?

Also, are all knock sensors created equally? Or some more sensitive? What should I look for as an alternative?

Any help thoughts or suggestions are greatly appreciated as I am in a bind here. Thanks in advance.


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## smj999smj (Jan 1, 2006)

Nissan used a "donut style" knock sensor on most of it's later models. Part #: 22060-30P00 runs about $168 from Nissan. That being said, I'm not sure how effective it would be as they give no resistance values to compare. It "might" work...

The option I would consider is getting the motor mount (and probably the crossmember)out of the way, carefully heating the area of the block that the sensor screws into with an oxy-acetylene torch and carefully working it back and forth until it can be screwed out. I'm not saying this would be easy, but it would be the way to do it in an attempt to do it the right way.


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## Matt93SE (Sep 17, 2003)

I would recommend the same. relocating the knock sensor is a good way to do severe damage to the engine. there's a lot of engineering behind the mounting location of the knock sensor. hard to explain why, but consider the KS is essentially a microphone looking for a certain frequency vibration. If you mount the sensor in a location where those vibrations are damped through the rest of the block, even a brand new knock sensor won't do you any good.

it's best to put it back in the original location. see what you can do to get the old one out.


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## dkyuss (Jun 26, 2007)

Hmmm. Well I havent had a chance to get under her again. I lubed up the threads and she has been driven daily to work and back since last weekend so hopefully will be a little looser. I will see what I can do without ripping her apart. Thanks for the comments.


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