So I have noticed that my caspers knock gauge goes full red at the drop of a hat while pl shows only 1 or 2 esc counts. I have my cel light set to come on at 4 esc counts via my extender chip and it has never come on. I feel like I'm overreacting to the gauge and am wondering if I should just set a specific esc threshold and let off if I see that?
How many esc counts is bad?
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I got rid of my knock gauge along time ago. That's all it did was give false alarms.
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you say esc counts but you seem to have that and knock retard confused
an esc count is a running record of each knock event and adds 1 per each event up to 255 then back to 0, it could be from starter on startup or knock it doesnt care it just counts events
now depending on the esc severity and knock count rate of activity the ecu will pull timing , and you see this on scanmaster and powerlogger as degrees of retard
the casper led is typically set so it takes up to what equates to 4 degrees retard to go full red and it will light with less.. actually any activity, that doesnt mean that the ecu will act on that activity and retard timing
remember the knock sensor is basically just a microphone tuned to a particular frequency area by the esc module and what you see on powerlogger is an effect based on the chips decision to act on the info it sees , the chip may decide to ignore a signal that is not loud or repetitive enough but that doesnt mean the casper gauge is wrong , if there was no signal coming from the esc module the casper gauge would not light at all .
if the leds are lit it may be light knock but it is there either caused by tune or mechanical . the tune should be re-evaluated and see if it can be eliminated , if you are sure its mechanical then you will need to fix the mechanical issue or live with it .
now can you run with a little knock on the street due to higher timing (not lean as thats another thing) ..sure , car makers would tell you thats where they want their timing for emmissions , light knock is fine and they equiped cars with the knock sensor to allow the ecu to command as much timing as they could and then retard if it knock gets out of hand .. fine for the street in an NA car or when not in boost but at wot knock can be deadly to engines .
just because the chip doesnt act and pull as much timing as you would think it should based on the casper gauge, its still knock and its better to be aware of it as it happens then after the fact when all you can do is review the logs and wonder why the headgasket popped
i run one in all my cars especially with fast/xfi as that doesn't react to knock activity as you would think and alky wont give you a second chance at elevated boost levels
typically at the track I am only concerned what the caspers gauge does once i'm into third gear as gear changes and launches will typically result in some led activity even though the fast shows no knock on logs .
on the street normal driving the caspers led saw transitional knock activity that the fast didnt and that activity was then tuned out so it was real
an esc count is a running record of each knock event and adds 1 per each event up to 255 then back to 0, it could be from starter on startup or knock it doesnt care it just counts events
now depending on the esc severity and knock count rate of activity the ecu will pull timing , and you see this on scanmaster and powerlogger as degrees of retard
the casper led is typically set so it takes up to what equates to 4 degrees retard to go full red and it will light with less.. actually any activity, that doesnt mean that the ecu will act on that activity and retard timing
remember the knock sensor is basically just a microphone tuned to a particular frequency area by the esc module and what you see on powerlogger is an effect based on the chips decision to act on the info it sees , the chip may decide to ignore a signal that is not loud or repetitive enough but that doesnt mean the casper gauge is wrong , if there was no signal coming from the esc module the casper gauge would not light at all .
if the leds are lit it may be light knock but it is there either caused by tune or mechanical . the tune should be re-evaluated and see if it can be eliminated , if you are sure its mechanical then you will need to fix the mechanical issue or live with it .
now can you run with a little knock on the street due to higher timing (not lean as thats another thing) ..sure , car makers would tell you thats where they want their timing for emmissions , light knock is fine and they equiped cars with the knock sensor to allow the ecu to command as much timing as they could and then retard if it knock gets out of hand .. fine for the street in an NA car or when not in boost but at wot knock can be deadly to engines .
just because the chip doesnt act and pull as much timing as you would think it should based on the casper gauge, its still knock and its better to be aware of it as it happens then after the fact when all you can do is review the logs and wonder why the headgasket popped
i run one in all my cars especially with fast/xfi as that doesn't react to knock activity as you would think and alky wont give you a second chance at elevated boost levels
typically at the track I am only concerned what the caspers gauge does once i'm into third gear as gear changes and launches will typically result in some led activity even though the fast shows no knock on logs .
on the street normal driving the caspers led saw transitional knock activity that the fast didnt and that activity was then tuned out so it was real
I use it as my early detection system and it is a good thing to have. I am certainly not going to ditch it. That being said, it will go red really easy, like on a hard launch, spinning the tires, or sometimes on a hard downshift when I get into it. The problem is that the light holds for awhile so if I get false knock due to some tire spin I am nervous to stay in it because the false alarm has rendered it useless for the rest of the run. I have no issues with anything rubbing either. I run a TT chip and it seems to react to knock pretty well. Typically my logs either show no knock or maybe a degree pulled when this thing goes red. My point was asking if I can use my feature in my chip to illuminate the CEL light as a secondary warning system. If the Caspers gauge lights up on some tire spin but the CEL never comes on when set to a low count I can hopefully feel a little safer.
H
Heisenberg
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I enjoyed pacecarta's thoughtful reply.
I listened to some respected guys a while ago and banished the words "false knock" from my vocabulary.
Even though it very well might be true - to assume so they say is dangerous.
I'm constantly hunting and finding various sources of mechanical clanging.
I listened to some respected guys a while ago and banished the words "false knock" from my vocabulary.
Even though it very well might be true - to assume so they say is dangerous.
I'm constantly hunting and finding various sources of mechanical clanging.
pacecarta, I finally got to read through your entire post uninterrupted and got to the part where you really rely on the gauge in 3rd at the track. Makes sense. I guess my point of this thread was to ask how many esc counts in a short period of time is bad. Mine increments 2 counts in a couple seconds and my gauge goes red.
I read through my TT chip instructions again, and even though it reads like it is talking about counts, I realized they are talking about knock retard. So I guess I have never hit 4 degrees, so that is a good thing. I think I may set it for 2 degrees and see if I ever hit that. If my Caspers goes red after frying the tires in 1st and the CEL light does not go on, I should be in the clear and it will reset by the time I hit 3rd.
I read through my TT chip instructions again, and even though it reads like it is talking about counts, I realized they are talking about knock retard. So I guess I have never hit 4 degrees, so that is a good thing. I think I may set it for 2 degrees and see if I ever hit that. If my Caspers goes red after frying the tires in 1st and the CEL light does not go on, I should be in the clear and it will reset by the time I hit 3rd.
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i would expect knock retard when braking tires loose but pay close attention to the tune at that point and make sure its not going lean and knocking , if tune looks good then the knock is drive line related and you can dismiss it , if its going lean you need to fix the tune even if it doesn't get rid of the knock
because drive line can create some strange noises which could get picked up as knock eric uses a 1st gear launch ignore feature in his TT chips that wont pull timing at launch (usually under 35mph ).... so you could see activity on the caspers that the chip wont display on scanmaster because its setup to ignore
because drive line can create some strange noises which could get picked up as knock eric uses a 1st gear launch ignore feature in his TT chips that wont pull timing at launch (usually under 35mph ).... so you could see activity on the caspers that the chip wont display on scanmaster because its setup to ignore
RmvBfrFlght
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Don't go by knock counts, go by knock retard (spark retard). The reason is that there can easily be knock retard without the the ALDL link or the PL showing additional knock counts.
This will occur because the knock counter (PA3) is a 16-bit value (2 bytes). Both the PL and the ALDL link only show the upper byte of the knock counter. There can be several degrees of knock retard with no counts showing.
This is why the knock gauge goes full red when the PL is only showing a count or maybe two. The lower byte (LSB) of the knock counter is incrementing, with spark advance being reduced (knock retard), but the upper byte (MSB, the one we see) hasn't moved yet. Need to get 256 counts before a single count gets registered on the upper counter byte.
How the ESC system (electronic spark control, the knock retard system), works at a hardware level is: there is a 16-bit (2 bytes) hardware counter that runs when the ESC filter reports knock. It runs are 64 KHz, or, 65,536 times a second. The signal from the ESC module is basically digital, it just goes low when reporting knock.
The lower byte (LSB) of the counter, the one we don't see, increments first. After 256 counts then the upper byte gets incremented (MSB), the one we see, to actually report something. The lower byte then rolls over to/past zero and starts over.
In that time the ECM can be pulling spark advance. I say 'can' because under various circumstances knock retard can be held off.
RemoveBeforeFlight
This will occur because the knock counter (PA3) is a 16-bit value (2 bytes). Both the PL and the ALDL link only show the upper byte of the knock counter. There can be several degrees of knock retard with no counts showing.
This is why the knock gauge goes full red when the PL is only showing a count or maybe two. The lower byte (LSB) of the knock counter is incrementing, with spark advance being reduced (knock retard), but the upper byte (MSB, the one we see) hasn't moved yet. Need to get 256 counts before a single count gets registered on the upper counter byte.
How the ESC system (electronic spark control, the knock retard system), works at a hardware level is: there is a 16-bit (2 bytes) hardware counter that runs when the ESC filter reports knock. It runs are 64 KHz, or, 65,536 times a second. The signal from the ESC module is basically digital, it just goes low when reporting knock.
The lower byte (LSB) of the counter, the one we don't see, increments first. After 256 counts then the upper byte gets incremented (MSB), the one we see, to actually report something. The lower byte then rolls over to/past zero and starts over.
In that time the ECM can be pulling spark advance. I say 'can' because under various circumstances knock retard can be held off.
RemoveBeforeFlight
Alright, so I set my knock light to 2 degrees. Beat on it a bit and the light never came on. I did have one time where my Caspers gauge went yellow, but I was not able to reproduce it. Another time it went red, but I was laying down some thick black tracks. It seems to be very sensitive to tire spin. I think that if it acts up on a launch I will rely on my CEL light set to 2 degrees and then rely on the Caspers gauge as soon as it resets from that.
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i like the caspers but the hold time before reset should be shorter
The gauge works well for my SVO as I have no possible way other than that to monitor knock. She is a fickle beast. On the Buick it was just too sensitive and I found my eye going there more than I liked. Butt, powerlogger, scan master and ear work fine for me.
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Yeah it would be awesome if you could adjust the hold to your liking.
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