"flat response" knock sensors

They go by many names, P01, P59, VPW, '0411 etc. Also covering E38 and newer here.
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NSFW
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"flat response" knock sensors

Post by NSFW »

I've got an engine on the way for my 2002 Corvette which uses a gen-IV block with gen-III crank and cam sensors, and I just realized that the block uses the newer-style "flat response" knock sensors, which apparently were used on some gen-III vehicles before the gen-IV change.

I've ordered the sensors and wiring harness, but the tune will need some changes as well.... I found the table for "Knock Sensor Type" but there are a ton of knock related tables and I wonder what else needs to change. Also, do the new sensors use the same pins on the PCM connector?

If anyone knows of a vehicle that came from the factory with a P59 OS and the new-style knock sensors, I'd love to know about it.

The car will be tuned by a local shop, and they've got a great reputation, but I'm not sure it's reasonable to expect the tuner to be familiar with random stuff like this.

Thanks in advance for any suggestions.
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kur4o
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Re: "flat response" knock sensors

Post by kur4o »

used on ls2 and e40 up

12623730 02.383 SENSOR, KNOCK (MATING CONN W/LEADS USE 13580877) (ACDelco #213-1576) CK1 (L92) 2007-2008 02

attached at side of the block with a bolt.

I can`t see an application for earlier pcm.
There is a setting for flat response in p01, but all others table related to knock needs to be borrowed from later pcm based on the block.
And still nobody knows how it will turn out at the end.
In-Tech
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Re: "flat response" knock sensors

Post by In-Tech »

This isn't going to help much but I just re-drill and tap the block for the early knock sensor. I keep the correct drill bit and a regular and bottoming tap.
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NSFW
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Re: "flat response" knock sensors

Post by NSFW »

I found some info about the pins from EFI Live, via LS1 Tech:
This is what efilive shows:
"The PCM can be used with two types of knock sensors, this parameter allows you to select which type of sensor is fitted to the engine.
The standard LS1 sensor is a resonant type, these sensors are connected like so -
Sensor Bank #1 - J1,pin51
Sensor Bank #2 - J1,pin11

If the engine is fitted with flat response sensors (like the LS2 uses), then the connections are like so -
Sensor Bank #1 GND - J1,pin49
Sensor Bank #1 Signal - J1,pin09

Sensor Bank #2 GND - J1,pin50
Sensor Bank #1 Signal - J1,pin10
I'm pretty sure that's a typo on the last line - Bank #2 signal.
Please don't PM me with technical questions - start a thread instead, and send me a link to it. That way I can answer in public, and help other people who have the same question. Thanks!
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NSFW
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Re: "flat response" knock sensors

Post by NSFW »

Conversion harnesses:

https://www.wiringspecialties.com/lsx-g ... n-adapter/

https://www.racetronix.biz/p/knock-sens ... 2/ls1-ksrh

And the knock sensor part number appears to be 12623730. It was used on a lot of GM V8s from 2005-2020 and maybe beyond.
Please don't PM me with technical questions - start a thread instead, and send me a link to it. That way I can answer in public, and help other people who have the same question. Thanks!
In-Tech
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Re: "flat response" knock sensors

Post by In-Tech »

I've not done what you are attempting with the p01 and p59, and I hope it can end up as easy as it sounds. It's definitely more than just a switch setting, many many more variables. I spent a solid month on the dyno draining the tank back and forth from race gas and 87 octane to get the mefi3(delphi too) to get my knock crap right and distinguish noise. I am eager to hear of your results if you do attempt. Honestly why I bought drill and tappys instead of attempting and/or killing a different combo. It's not a perfect but just a compromise. The mefi4 is similar to a '94 LT1 puter and just like all of the newer stuff(old huh?) you can choose the bank for each sensor along with the firing order, and also what time during combustion it listens. GM stuff is bad the fack ass.
aaronc7
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Re: "flat response" knock sensors

Post by aaronc7 »

Been quite a while ago now and I can't dig up all the good info I found at the time...but I basically came to the conclusion that I should just stick to stock sensors/stock location if I wanted to keep any sort of reliable knock system. As it turned out, the block I got was gen3 style so it wasn't an issue but.... didn't seem to be a real working solution to running the newer sensors with gen3 PCM and/or non-stock location. And I certainly don't have the means or capacity to properly "tune" the new sensors either. I don't think I've seen any knock ever on my new motor so who knows if it's even working now.... lol.
persingc
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Re: "flat response" knock sensors

Post by persingc »

Following. I'm curious as to what you get figured out.
Rickky bobby
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Re: "flat response" knock sensors

Post by Rickky bobby »

company Ict Billet has knock sensor relocation brackets. it puts the knock sensor 1 on driverside and 1 on passengerside of the block. uses factory knock sensor from valley pan in block. then can use a smoothe valley pan with no holes for knock sensor. Ict Billet also sells the wire extention for the sensors. edit: gen 3
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NSFW
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Re: "flat response" knock sensors

Post by NSFW »

I'm still waiting for the shop that will do the engine installation, so this isn't a proven plan yet, but...

Part number for the new flat-response sensors: 12623730
Adaptor harness: https://www.amazon.com/dp/B082WMTSN5/

Repinning the sensor signals to:
Sensor Bank #1 Signal - J1, pin 09 - was pin 51
Sensor Bank #2 Signal - J1, pin 10 - was pin 11

And I've copied a bunch of knock sensor tables from the 2165 V6 ROM that was posted here:
viewtopic.php?f=42&t=7676

Checked the box for the knock sensor type, of course.
Changed "filter" from 2 to 1.
Initial threshold from 255 to 110mv
Minimum threshold to 70 from 230mv
Max threshold from 290 to 120mv
Knock sensor multiplier tables shaped like the flat-response ROM.
Background noise filter changed to 1.0.
Knock sensor multiplier by RPM table: all cells changed from 17 to 24

I'm open to ideas on what to do differently.

I'm taking the car to a shop that does a lot of performance work on much older cars so I'm planning to ask the tuner to listen for knock as he would for an engine that doesn't have knock sensors. Hopefully we'll get some idea of whether the revised sensors are working reasonably well or not. If they're not, I'll ask him to tune without them (using knock ears or whatever) and I'll be looking for a way to wire the sensors up to my stereo so I can figure out how to get the PCM to make use of the signals.

It's a little weird that there are at least two wiring harnesses on the market for the updated sensors, but very little information available about how to get the PCM to work properly with the updated sensors.
Please don't PM me with technical questions - start a thread instead, and send me a link to it. That way I can answer in public, and help other people who have the same question. Thanks!
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