changing knock retard gain??
changing knock retard gain?? sometimes I get periodic knock at 4k, timing up or down sometimes it happens sometimes not, but the kr very slowly drops but by then I'm allready going into the next gear, so its basically dropping timing from 4k up and I can feel a loss of power, sometimes its 1-2deg. sometimes 3-4, I'm boosted, 5psi running 91octaine and I could see that being the problem but is there any way to make it bring the timing back to normal alot quicker? like by the next 4200 rpm range or something?, maybe I could set the max knock at 4200 to 0 and leave the rest where they are, and if there was still knock @ 4400 it would tell me... I dont know.....
does anybody understand what I mean...
plugs are good, compression is good all cylinders, 11.0afr wot so the combustion chamber could be getting a little black...
does anybody understand what I mean...
plugs are good, compression is good all cylinders, 11.0afr wot so the combustion chamber could be getting a little black...
I'm not accually getting detonation, but once in a while I'll get the kr, the engine is smooth and crisp, I think its a false knock but just incase I dont want to do anything stupid.... seems like the harder I drive it the better it runs.... weird... guess I just have to pound it more, lol
I'd say that your knock is most likely real and not false. I've only seen false knock on 98's or when something like exhaust is hitting the car. Every turbo ls1 i've tuned seems to be really sensative to detonation in the 3800-4200 range. I know mine is, but I've tuned it out.
I actually increase the gain so it pulls more timing if it sees knock. Turning it off in that range is a really bad idea.
To find out if it's false knock fill up with some 100 octane and see if you still get knock. Just because you can't hear it doesn't mean it's not detonating the **** out of the motor.
I actually increase the gain so it pulls more timing if it sees knock. Turning it off in that range is a really bad idea.
To find out if it's false knock fill up with some 100 octane and see if you still get knock. Just because you can't hear it doesn't mean it's not detonating the **** out of the motor.
TECH Regular
Joined: Feb 2003
Posts: 451
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From: Spring Hill, TN
Like he said ^ you really can't count on hearing the knock. Use his experiment to determine if it's real or not.
Then, assuming it's real and that you only want to recover faster after you are out of the knock range, then my understanding is that the recovery rate is what you want to mess with.
And as long as you are in there tuning, perhaps you should fatten the mixture a bit in that target RPM range, or just drop an additional degree of advance.
Then, assuming it's real and that you only want to recover faster after you are out of the knock range, then my understanding is that the recovery rate is what you want to mess with.
And as long as you are in there tuning, perhaps you should fatten the mixture a bit in that target RPM range, or just drop an additional degree of advance.
but couldnt I also get knock from dropping too much timing, on this last tune its @ 13* in the 4k block, and af is in the high 10's, iat's in the low 60's, boost 5psi.... I planned on turning up the boost to 6 or 7 if I could get this worked out, but I'd have to drop the timing another 1-2* right?........ I'll try the 100 octaine...
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Launching!
Joined: Sep 2004
Posts: 248
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From: Honolulu-Hi
I'm certainly no tunning expert,but i remember some reporting the early c5s had the rumbling idler pulley on the serpentine belt that triggered the knock sensors.
Or the other early c5 KS problem,where you have to remove the intake,and build a moat around the rear sensor because the water gets in there and ruins the sensor.
Damn Assasin,didn't you live in Maui not to long ago?Looking for z rims...?
Or the other early c5 KS problem,where you have to remove the intake,and build a moat around the rear sensor because the water gets in there and ruins the sensor.
Damn Assasin,didn't you live in Maui not to long ago?Looking for z rims...?
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Verdad Gallardo haha, yeah kauai... I finally got the z rims I wanted over here and mounted some kumho v710's on um...
what was the fix for the idler pulley, get a new one?, I know when the engine is running I can hear that thing just a little...
what was the fix for the idler pulley, get a new one?, I know when the engine is running I can hear that thing just a little...
Launching!
Joined: Sep 2004
Posts: 248
Likes: 0
From: Honolulu-Hi
Ya,they have a updated part number.Don't have it off hand,but i'm sure the dealers have sold,or tossed all the 97-99 idlers by now.Ecklers has 2 different part numbers.Or aftermarket.
Man,why did you move?Work?At least you kept the car.Now your getting into tunning sweet....you know you'll need it if you ever come back this way.
Man,why did you move?Work?At least you kept the car.Now your getting into tunning sweet....you know you'll need it if you ever come back this way.
TECH Regular
Joined: Feb 2003
Posts: 451
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From: Spring Hill, TN
Idler pulley or not, the test is the 100 octane. Don't just throw parts at it.
And no, removing timing cannot contribute to knock, but you might lose power. Have you pulled timing in the program since you boosted it? Boosted motors require less timing.
And no, removing timing cannot contribute to knock, but you might lose power. Have you pulled timing in the program since you boosted it? Boosted motors require less timing.
Launching!
Joined: Sep 2004
Posts: 248
Likes: 0
From: Honolulu-Hi
Originally Posted by jyeager
Idler pulley or not, the test is the 100 octane. Don't just throw parts at it.
And no, removing timing cannot contribute to knock, but you might lose power. Have you pulled timing in the program since you boosted it? Boosted motors require less timing.
And no, removing timing cannot contribute to knock, but you might lose power. Have you pulled timing in the program since you boosted it? Boosted motors require less timing.
Bulletin: Audible Spark Knock (Detonation),
Subject: Audible Spark Knock (Detonation)(Replace Rear Bank Knock Sensor and RTV Area Around Sensor)
Source: Chevrolet Dealer Technical Service Bulletin
Number: 02-06-04-023
Models: 1998-2002 Chevrolet Camaro, Corvette, 1998-2002 Pontiac Firebird
with 5.7L Engine (VIN G -- RPO LS1)
1999-2002 Chevrolet and GMC C/K Pickup and Utility Models (Avalanche, Silverado, Sierra, Tahoe, Suburban, Yukon, Yukon XL, Yukon Denali, Yukon Denali XL) with 4.8L, 5.3L or 6.0L Engine (VINs V, T, Z, N, U -- RPOs LR4, LM7, L59, LQ9, LQ4)
Condition:
Some customers may comment on a mild to severe engine ping (commonly referred to as spark knock), usually worse during acceleration and/or an illuminated MIL. Upon investigation, the technician may find DTC P0332 set.
Cause:
This condition may be the result of corrosion of the rear bank knock sensor due to water intrusion into the sensor cavity. This condition is more apparent on vehicles in which customers frequently wash the engine compartment.
Correction:
Replace the rear bank knock sensor and build a dam (wall) around the sensor using RTV to divert water away from the sensor. Use the procedure and part number listed below.
update: https://ls1tech.com/forums/pcm-diagnostics-tuning/452617-f-kr.html
the 100octaine didnt help, I droped the timing even more, af is 11.0, still periodic knock, I'll check into the idler and the knock censors....
the 100octaine didnt help, I droped the timing even more, af is 11.0, still periodic knock, I'll check into the idler and the knock censors....