ST knock is the current knock detected by the PCM.
LT knock is a correction based on a history of knock. It's an adaption over time. I have not seen anything but "0" for this value on the Neon SRT4, so it may not be supported.
Fuel knock is described as the total of ST + LT knock. On the cars I've seen this always equals ST knock since LT is always 0.
Knock retard is described as the total commanded knock retard. Since I only know of ST and LT this would be the same as Fuel knock. All my logs have shown this to equal ST knock on the SRT4.
We added these to make them available for all the 2003+ Chrysler vehicles. LT knock my indeed indicate something if knock is bad enough, for a long period of time. I'd be interested to know if anyone gets a reading other than 0.
At this point it seems that you can watch ST, Fuel, or Total knock and get the same results in the SRT4.
ST knock is the current knock detected by the PCM.
LT knock is a correction based on a history of knock. It's an adaption over time. I have not seen anything but "0" for this value on the Neon SRT4, so it may not be supported.
Fuel knock is described as the total of ST + LT knock. On the cars I've seen this always equals ST knock since LT is always 0.
Knock retard is described as the total commanded knock retard. Since I only know of ST and LT this would be the same as Fuel knock. All my logs have shown this to equal ST knock on the SRT4.
We added these to make them available for all the 2003+ Chrysler vehicles. LT knock my indeed indicate something if knock is bad enough, for a long period of time. I'd be interested to know if anyone gets a reading other than 0.
At this point it seems that you can watch ST, Fuel, or Total knock and get the same results in the SRT4.
Todd
well now that I read this I'll tell you LT Knock does register on the SRT4. Plus your description makes more sense as to what I was seeing...
When tuning and getting aggressive I did hit a postive value on LT Knock (1.0 - 3.0 range). Then I backed down the tune and as soon as I hit part throttle boost it'd jump immediately to 1.5 which seemed weird. It'd stop doing that once you recycled the ignition. I think now I understand what was happening if it was pushing it up because it's an average value.
So by your description I should set the annunciator to ST Knock or Knock Retard and to around 2.0 then right?
well now that I read this I'll tell you LT Knock does register on the SRT4. Plus your description makes more sense as to what I was seeing...
When tuning and getting aggressive I did hit a postive value on LT Knock (1.0 - 3.0 range). Then I backed down the tune and as soon as I hit part throttle boost it'd jump immediately to 1.5 which seemed weird. It'd stop doing that once you recycled the ignition. I think now I understand what was happening if it was pushing it up because it's an average value.
So by your description I should set the annunciator to ST Knock or Knock Retard and to around 2.0 then right?
That's good to know. I don't get much knock, maybe 3 degrees on my '04, and LT never shows anything but "0". The LT term is like a knock learn factor, its value is automatically reduced from the ignition advance whether you have knock or not, until certain criteria are met that allows it to add this back. If you started running 87 octane for example, I would expect LT to start showing a value. Once you put 93 back in the PCM would realize eventually that it could add the timing back and LT would go to zero.
ST or total is the most critical, because it shows what happening at that instant.
okay cool I changed it to there...the last week or so I've had 0.0 KR on LT and across the board because I got the tune right...but during the initial tuning (on stock fuel I might add) the ECU did get a little pissy with me (especially in the timing department).
SO...my best bet to monitor knock is to set "ST Knock" then to 2.4 on the annunciator if I want to watch the knock correct? I've heard 3.0 KR is the max that's acceptable on pump gas agree?
uncommon might be a good person to ask after he bent (and eventually threw) a rod. dunno if he data logs though.
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uncommon might be a good person to ask after he bent (and eventually threw) a rod. dunno if he data logs though.
hmm...I try to (and so far have been successful) at keeping the knock retard reading 0.0 of late and timing in the high 20s to low 30s at full throttle on stock fuel and 19-20psi fade to 14psi and AFRs in the 11s all the way from 2500 to 6200rpms with just a MAP clamp and a good chunk of bolt-ons.
hmm...I try to (and so far have been successful) at keeping the knock retard reading 0.0 of late and timing in the high 20s to low 30s at full throttle on stock fuel and 19-20psi fade to 14psi and AFRs in the 11s all the way from 2500 to 6200rpms with just a MAP clamp and a good chunk of bolt-ons.
might be time for me to do some cranking then too... dern wish the wideband would get here faster (and the cash to buy a gauge for it). how did you finally dial in your boost, 3rd gear pulls from low RPM?
might be time for me to do some cranking then too... dern wish the wideband would get here faster (and the cash to buy a gauge for it). how did you finally dial in your boost, 3rd gear pulls from low RPM?
to you for t3h good documentation of your setup.
I started with 2nd gear romps to get the voltage clamp down to a respectable area on the AFR (aka just see what the Aeroforce reads as boost from the MAP). Then fine tuned it in 3rd gear...once I felt it was fine I got an open patch and took her to 130mph (end of 4th). What I do notice is how drastic the AFR can change with weather changes so I'm glad to say I have an in-cabin MAP clamp as I can tune the car on the fly w/o getting out of the car.
Seems like 15.5-15.9psi (whatever that equals in voltage) works best for me.
okay cool I changed it to there...the last week or so I've had 0.0 KR on LT and across the board because I got the tune right...but during the initial tuning (on stock fuel I might add) the ECU did get a little pissy with me (especially in the timing department).
SO...my best bet to monitor knock is to set "ST Knock" then to 2.4 on the annunciator if I want to watch the knock correct? I've heard 3.0 KR is the max that's acceptable on pump gas agree?
3 is the most I want to see, and this is where I have the annunciator set at.
I have mine set to KR and i am seeing 7 counts. I saw 2KR ar 3psi today. whats the deal? I just checked my car and i only have KR and Knock volts no ST or LT knock
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Last edited by AnotherNeon : 06-18-2008 at 06:05 PM.
I have mine set to KR and i am seeing 7 counts. I saw 2KR ar 3psi today. whats the deal? I just checked my car and i only have KR and Knock volts no ST or LT knock
Is this a question? I don't understand what you're asking.
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Clarification on reading knock from gauge
Linear Mode
