Does the sctx3 have a kam reset function?
I havent looked for it. Or are you pulling fuse 47 to reset it?
Active knock
- Thread starter MooDy5.0
- Start date
I havent looked for it. Or are you pulling fuse 47 to reset it?
You have to be running a newer version of firmware on the X3 but it does have it under special operation or something like that. I want to say it showed up around the beginning of this year.
Ok, let met share 2 experiences to shed some light on this:
EXPERIENCE #1
When I was datalogging one day I noticed I had +1.3 degrees of Knock (in the middle of the band;rest of the band was adding timing) when going WOT from 2500rpm to redline. The temperature was 88 degrees and I was acclerating on to a freeway on-ramp.
Later that day in the evening I dataloged again, same on-ramp, same gear, same RPM, SAME GAS (obviously), but now the temperature was 67 degrees (20 degrees cooler). I had only +.3 degrees knock (almost nothing) and the car was adding a little more timing throughout the band. This is all off of CA 91 ocatane.
Moral of the story: Octane is not the "be all, end all" when it comes to timing. Temperature, load, etc. all have a huge impact. If you are seeing 3 or 4 degrees timing being pulled throughout most of the run, yeah thats a fair amont of power being pulled (also depends on what spark is being commanded as well). But for me .5- 1.0 degree's being pulled, well lets just say I won'T loose sleep (Ill probably find another gas station if it really bothers me, there is just so much crap gas out there)
EXPERIENCE #1
When I was datalogging one day I noticed I had +1.3 degrees of Knock (in the middle of the band;rest of the band was adding timing) when going WOT from 2500rpm to redline. The temperature was 88 degrees and I was acclerating on to a freeway on-ramp.
Later that day in the evening I dataloged again, same on-ramp, same gear, same RPM, SAME GAS (obviously), but now the temperature was 67 degrees (20 degrees cooler). I had only +.3 degrees knock (almost nothing) and the car was adding a little more timing throughout the band. This is all off of CA 91 ocatane.
Moral of the story: Octane is not the "be all, end all" when it comes to timing. Temperature, load, etc. all have a huge impact. If you are seeing 3 or 4 degrees timing being pulled throughout most of the run, yeah thats a fair amont of power being pulled (also depends on what spark is being commanded as well). But for me .5- 1.0 degree's being pulled, well lets just say I won'T loose sleep (Ill probably find another gas station if it really bothers me, there is just so much crap gas out there)
Experience #2
AED dyno tune:
Took my car to Shaun at AED for dyno tune. He didn't like that I had 1.5 degrees of Knock in the higher RPM's. Bad Gas? I told him I was using 76 and he said that was a good brand (he also mentioned Costco as being good to; I personally havent tried this yet). He felt that maybe there were carbon deposits in the engine, and to help "clean" them out, he basically beat the piss out of my car on the dyno. 6 or 7 part throttle or WOT pulls to get the engine real hot to "melt" all the carbon off.
Result: No knock. In fact Knock sensors were adding more than 3 degrees of time throughout the run.
Moral of story: Maybe we all just need to beat the piss out of cars (as if we dont already
) and get good oil seperators.
I'm not a mechanic or a technician, but I hope my experiences will shed some light and help some people, because I know knock issues drive people crazy.
AED dyno tune:
Took my car to Shaun at AED for dyno tune. He didn't like that I had 1.5 degrees of Knock in the higher RPM's. Bad Gas? I told him I was using 76 and he said that was a good brand (he also mentioned Costco as being good to; I personally havent tried this yet). He felt that maybe there were carbon deposits in the engine, and to help "clean" them out, he basically beat the piss out of my car on the dyno. 6 or 7 part throttle or WOT pulls to get the engine real hot to "melt" all the carbon off.
Result: No knock. In fact Knock sensors were adding more than 3 degrees of time throughout the run.
Moral of story: Maybe we all just need to beat the piss out of cars (as if we dont already
) and get good oil seperators. I'm not a mechanic or a technician, but I hope my experiences will shed some light and help some people, because I know knock issues drive people crazy.
Last edited:
Ok I will look for it but mine might have the older firmware.
Thanks for sharing 50blackout
Do u think if i do a KAM reset every time will effect anything?
Just checked. My SCT does clear KAM memory. It only takes a couple of seconds. I guess I will keep the SCT in the car and clear it on occasion.
Well one thing I do know is that if we don't reset every now and then things are affected negatively.
Exactly how I see it. If I would have continued to do WOT pulls not knowing that my fueling was extremely lean I could have easily hurt my motor. Thats why gauges are a must especially when running boost.
For sure Tron. I went with a single Aeroforce gauge and now I wish I would have bought the dual setup.
Last edited:
Yes as 50Blackout has mentioned it seems heating the engine up has been another remedy for cleaning up the knock activity *IF* it's not actually due to fuel quality. Since 50Blackout was on the dyno where I did this procedure, I've had customers around the country do the same with similar results, but not all have been successful FYI. Others have done a KAM resets with no changes in knock, and a few have seen MAJOR changes in knock activity after a KAM reset.
We know Long term adaptive knock is not stored in Keep Alive Memory, but it does not look as though Short term Adaptive Knock IS stored in KAM. This would explain why *Some* see changes after at KAM reset and others do not.
Unfortunately we do not have all the answers. These Copperhead ECU's are very complicated and we are likely to still be learning new aspects of what it does and it's capabilities for years to come.
Blackout is also correct about fuel quality. Octane is an indication of the quality of fuel, but its the RVP that really matters here. Additive packages in fuels that lower the RVP are more prone to detonation than fuels with higher RVP. Torco actually works well to raise the RVP of a fuel and it's why we use it to offset winter blend, but it's not a replacement for Race gas as it does not actually raise the Octane as advertised. It raises the RVP and makes the fuel 'act like' higher octane fuel.
We know Long term adaptive knock is not stored in Keep Alive Memory, but it does not look as though Short term Adaptive Knock IS stored in KAM. This would explain why *Some* see changes after at KAM reset and others do not.
Unfortunately we do not have all the answers. These Copperhead ECU's are very complicated and we are likely to still be learning new aspects of what it does and it's capabilities for years to come.
Blackout is also correct about fuel quality. Octane is an indication of the quality of fuel, but its the RVP that really matters here. Additive packages in fuels that lower the RVP are more prone to detonation than fuels with higher RVP. Torco actually works well to raise the RVP of a fuel and it's why we use it to offset winter blend, but it's not a replacement for Race gas as it does not actually raise the Octane as advertised. It raises the RVP and makes the fuel 'act like' higher octane fuel.
Thanks Shaun for helping us, i want to ask u that there is something touching underneath the car and making the knock , i tried to figure out the location for 3 months and i could not. By KAM reset the knock will disappear ,So can i do a KAM reset then data log and tuning the car? I don't mind to do a KAM reset daily if i have
I want to update what happened to me with KAM reset. The first time I did it I drove it 15 miles or so and did a WOT pull and all my KR disappeared. The next day I did another log and the KR returned on the same tank of gas, same road. Be aware that even though you clear the KAM and it appears to go away briefly doesnt mean you're in the clear. You need to wait a few days and log again and make sure it's still good. A KAM reset is a good way to make your computer recognize new gas as you test but it is not a magical KR erase button by any means.
when you load a tune does that clear the KAM? or does this need to be done in addition
According to Shaun, loading a tune does NOT clear the KAM.
Hmmm. I'm pretty sure it cleared the kam when I reloaded my tune. My fuel trims, learned knock etc all went back to 0. Unless that isn't everything the kam has stored.
Last edited:
what if you go from stock to a tune?
Users who are viewing this thread
