knock sensors
Thread Starter
Advanced
Joined: Jan 2007
Posts: 81
Likes: 3
From: Rocky Hill CT
knock sensors
I have a 1998 C5, A4, and just bought an LS3 crate engine for it. I am trying to get everything together before I make the swap. I ordered several harnesses from Summit, and one that I received was an extension harness for the knock sensors. This harness will plug into the the connections already installed on each side of the block. Originally I thought this was great, as it plugged right in for a neat installation. But, I have recently read that the computer may not read the signal properly, and I should instead install original style knock sensors (the type which were installed in the valley) on the sides of the block. Anybody with any information about this would be appreciated.
Racer
Joined: Feb 2014
Posts: 257
Likes: 45
From: Finland
You have to use original knock sensor. So you have to drill and make new threads side of block.
https://www.google.com/search?q=ls1+...Weta_-Y6MPbU2M
https://www.google.com/search?q=ls1+...Weta_-Y6MPbU2M
Melting Slicks
Joined: Nov 1999
Posts: 2,346
Likes: 856
From: MI
Cruise-In VI Veteran
Great read here
Getting a Modern LS3 into Your C5 is Easier Than You Think
http://www.superchevy.com/how-to/engines-drivetrain/1603-getting-a-modern-ls3-into-your-c5-is-easier-than-you-think/
cheers,
GOOSE
Getting a Modern LS3 into Your C5 is Easier Than You Think
http://www.superchevy.com/how-to/engines-drivetrain/1603-getting-a-modern-ls3-into-your-c5-is-easier-than-you-think/
cheers,
GOOSE
Last edited by 69; Dec 26, 2018 at 08:34 AM. Reason: Spel
Drifting
Joined: Feb 2001
Posts: 1,768
Likes: 297
From: Plano TX
You have to use original knock sensor. So you have to drill and make new threads side of block.
https://www.google.com/search?q=ls1+...Weta_-Y6MPbU2M
https://www.google.com/search?q=ls1+...Weta_-Y6MPbU2M
Great read here
Getting a Modern LS3 into Your C5 is Easier Than You Think
http://www.superchevy.com/how-to/eng...han-you-think/
cheers,
GOOSE
Getting a Modern LS3 into Your C5 is Easier Than You Think
http://www.superchevy.com/how-to/eng...han-you-think/
cheers,
GOOSE
Does it make a difference? Is one versus the other the root of the KR issue?
Thread Starter
Advanced
Joined: Jan 2007
Posts: 81
Likes: 3
From: Rocky Hill CT
As it turns out, I can use the Casper harness using plugs already installed on the LS3 crate engine. As long as the tuner is aware, those sensors will work fine. There is no need to drill and tap anything. A tech from "Injection Connection" out of Georgia, who has done about 40+ of these conversions, recommended that I just turn them off completely. His position is that they are way too sensitive, and driving with a lap top will show that every pot hole, or suspension bump triggers a retard in timing.
Le Mans Master
Joined: Aug 2005
Posts: 5,375
Likes: 328
From: CA.
St. Jude Donor '13-'14-'15
As a last resort most all tuners can adjust the "knock sensor" tables in your existing ECM tune--
Whether they need to be "sensitized" OR "de sensitized" This depends if the tuner hears real knock or is getting false knock
Whether they need to be "sensitized" OR "de sensitized" This depends if the tuner hears real knock or is getting false knock
Acct Suspended APR 2026 by request
Joined: Dec 2010
Posts: 10,367
Likes: 1,272
2020 Corvette of the Year Finalist (performance mods)
C5 of Year Winner (performance mods) 2019
personally I wouldn't want to have them turned off on my car... if you don't have enough octane and/or your tune is on the edge and something goes wrong then you will be buying another ls3 lol
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Le Mans Master
Joined: Aug 2005
Posts: 5,375
Likes: 328
From: CA.
St. Jude Donor '13-'14-'15
Sensitizing OR de sensitizing the knock tables does NOT turn them OFF----It changes the frequencies where the sensors pick up detonation-------------------------
I agree about not turning them OFF as well ---Best only done on a race only application using race fuel all the time--
I agree about not turning them OFF as well ---Best only done on a race only application using race fuel all the time--