LS1 knock sensor question?
12-16-2010, 07:12 PM
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LS1 knock sensor question? well i am changing out my knock sensors and i want to know if thay are different? one of them has 3090-1f and the other one has 0139-1f. i had them both in my hand and i know witch one went to the front.i got side tracked and didnt remember witch one was for the front. i am pretty sure the 3090 was in front but not 100% sure. so i was wondering if it matters?
12-16-2010, 09:51 PM
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They are the same it does not matter... I would recommend changing the wiring harness pigtail out while your at it it does not cost much more and they are a known problem.
12-16-2010, 11:50 PM
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well i found out my wiring harness is messed up. about 3 months ago i put new sensors and wiring harness. well i changed out my ls1 intake to a ls6 and didnt know it pinched my wires. so now going to just get a harness and do a lil grinding to the intake
12-17-2010, 12:20 AM
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rite on---
I would suggest you "build a dam " around them also, do a search
" dam around knock sensors ls1"
good luck Johnny
knock sensor - LS1 Performance Information
10 posts - 6 authors - Last post: Jul 1
knock sensor General Help. ... >>>>>>>There is a gm bulletin that says when you replace your sensors you should make a dam of rtv around the holes ...
www.ls1.com/forums/showthread.php?p=2373928 - Cached
12-18-2010, 04:10 PM
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12-18-2010, 05:27 PM
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^^^^^
rite on---
I would suggest you "build a dam " around them also, do a search
" dam around knock sensors ls1"
good luck Johnny
knock sensor - LS1 Performance Information
10 posts - 6 authors - Last post: Jul 1
knock sensor General Help. ... >>>>>>>There is a gm bulletin that says when you replace your sensors you should make a dam of rtv around the holes ...
www.ls1.com/forums/showthread.php?p=2373928 - Cached
rite on---
I would suggest you "build a dam " around them also, do a search
" dam around knock sensors ls1"
good luck Johnny
knock sensor - LS1 Performance Information
10 posts - 6 authors - Last post: Jul 1
knock sensor General Help. ... >>>>>>>There is a gm bulletin that says when you replace your sensors you should make a dam of rtv around the holes ...
www.ls1.com/forums/showthread.php?p=2373928 - Cached
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12-18-2010, 11:09 PM
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same thing happened to me , I changed the wire once and the sensors twice still had a code, finally i erased the code with an OBD2 and the code never came back, three months later i had a real loud knock so yea i needed a new engine or rebuilt the same one. to this day i don't know if the sensors where doing their job letting me know i had a slight knock or what . not trying to scare you just get it looked at by a pro now or bitch like me later
12-24-2010, 03:58 PM
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got another question guys! witch one of the knock sensors is the # 1? i was thinking it was the one in the front of the motor but i am not not 100% sure!
12-31-2011, 11:21 PM
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if you can get your hand to it it is on the very back behind the intake just a little more to the left side in the very middle of the intake there are 3 vac lines the wireing connect is just to the driver side, get a good light and look,
why are you looking for the connection if you are going to change the knock sensors you will have no problem seeing the wireing with the intake removed
I suggest you change both sensors and the wiring pig tail and build a dam around them, I think the wire is about 30-40.00
IF YOU pull the intake be VERY carefull and do not break the OIL pressure unit just behind the intake about 50.00, the vac line going to the brake boster will catch it, if jou do break it you may want it buy the specal socket to use on it 15-25.00
when replacing the intake be sure and reconnect the 3 vac line the small one goes the the ac/heater control
as to the oil pressure unit I pulled my intake 4 times with no problem and on # 5 I broke it
Johnny
why are you looking for the connection if you are going to change the knock sensors you will have no problem seeing the wireing with the intake removed
I suggest you change both sensors and the wiring pig tail and build a dam around them, I think the wire is about 30-40.00
IF YOU pull the intake be VERY carefull and do not break the OIL pressure unit just behind the intake about 50.00, the vac line going to the brake boster will catch it, if jou do break it you may want it buy the specal socket to use on it 15-25.00
when replacing the intake be sure and reconnect the 3 vac line the small one goes the the ac/heater control
as to the oil pressure unit I pulled my intake 4 times with no problem and on # 5 I broke it
Johnny
01-11-2012, 10:04 AM
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Looks like I have to replace the sensor on mine (throwing a code on Bank1 sensor), anyone have the part number for the harness? I can't seem to find it on Rockauto. I can find single wire connectors, but not a harness that I am assuming connects both sensors.
01-31-2012, 11:11 AM
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LS1 Knock Sensor Issue Hi all; I found this post; like you, I am having the same problem with the Knock Sensor OBDII Code on a 2004 LS1 Silverado.
Following this post this seems like a very common problem and is typical of GM. As a prior ASE Shop owner (1982 to 1986) and then latter GM line mechanic (Pontiac 1986 to 1988) I saw similar problems with other sensors. It is as if GM by now has not figured out that pooled water and dripping antifreeze destroys sensors. You would think by now they would figure out to use shielding or weather proofing.
Your Harness Question: Lingenfelter has the harness. It is; GM LS1 Knock Sensor & Cam Sensor Adapter Harness
Part Number: CE-109081
(OTC) Your Price: $54.95
Link>> http://www.lingenfelter.com/mm5/merc...Store_Code=LPE
Caveat: I am not affiliated with Lingenfelter in anyway; …just know they have a good name in performance.
The GM Dealer should have the OEM pigtail you mentioned.
A knock sensor measures vibration (analog input) and produces an adjustment (digital input) to the timing section of the computer by square wave or sine wave clipping, or by ohms. During normal operation the computer advances the timing until engine pre-ignition (detonation or pinging) happens and then the computer reduces the timing advance. When the computer looses its ability to effectively control its timing, it can no longer effectively control proper run-ability.
I just picked up a Knock Sensor for ~$40.00 and then smacked in the head with 4.2 hour flat rate $$$ to replace it? And then do this again in the next 2 to 4 years?? There has to be a better solution.
I am thinking ~$150.00 a weekend 2 hrs and not remove the manifold is a better way?? I hope so! Whether it works or not, I will post the results when completed.
I am going to try to remote the knock sensors to pick up the vibration inputs as needed without having to deal with the current method GM uses.
Because GM is using two knock sensors, I am assuming an array input? …Maybe an AND Gate in the logic circuit? Does any one know?
Following this post this seems like a very common problem and is typical of GM. As a prior ASE Shop owner (1982 to 1986) and then latter GM line mechanic (Pontiac 1986 to 1988) I saw similar problems with other sensors. It is as if GM by now has not figured out that pooled water and dripping antifreeze destroys sensors. You would think by now they would figure out to use shielding or weather proofing.
Your Harness Question: Lingenfelter has the harness. It is; GM LS1 Knock Sensor & Cam Sensor Adapter Harness
Part Number: CE-109081
(OTC) Your Price: $54.95
Link>> http://www.lingenfelter.com/mm5/merc...Store_Code=LPE
Caveat: I am not affiliated with Lingenfelter in anyway; …just know they have a good name in performance.
The GM Dealer should have the OEM pigtail you mentioned.
A knock sensor measures vibration (analog input) and produces an adjustment (digital input) to the timing section of the computer by square wave or sine wave clipping, or by ohms. During normal operation the computer advances the timing until engine pre-ignition (detonation or pinging) happens and then the computer reduces the timing advance. When the computer looses its ability to effectively control its timing, it can no longer effectively control proper run-ability.
I just picked up a Knock Sensor for ~$40.00 and then smacked in the head with 4.2 hour flat rate $$$ to replace it? And then do this again in the next 2 to 4 years?? There has to be a better solution.
I am thinking ~$150.00 a weekend 2 hrs and not remove the manifold is a better way?? I hope so! Whether it works or not, I will post the results when completed.
I am going to try to remote the knock sensors to pick up the vibration inputs as needed without having to deal with the current method GM uses.
Because GM is using two knock sensors, I am assuming an array input? …Maybe an AND Gate in the logic circuit? Does any one know?
Last edited by foperfoauto; 02-01-2012 at 12:39 AM.
