In my experience, that is normal. It is not actual knock. The FBK sensor is picking up something else like your air conditioner or transmission clutter. If the FBK goes higher as you accelerate, then that might be a problem but for now, dont sweat it. It is called an anxietyport for a reason.
Feedback knock/Fine learn knock
I just received my COBB AP today. My car is currently bone stock (2017 STI) and I loaded the Stage 1 91 octane map. I noticed when monitoring my gauges I was getting some feedback knock/fine learn knock and wondered if someone could take at my logs and tell me if this is normal looking or something to be concerned about. Any help is appreciated as I am new to this.
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Thanks for the reply! Definitely not my air conditioner since I live in Canada and we're freezing up here right now haha, so very well could be the tranny then.In my experience, that is normal. It is not actual knock. The FBK sensor is picking up something else like your air conditioner or transmission clutter. If the FBK goes higher as you accelerate, then that might be a problem but for now, dont sweat it. It is called an anxietyport for a reason.
Surprised you got Fine Knock Learn so fast. In any case, believe it or not, what you're seeing is a good thing. In the sense that the ECU is learning your particular car and ironing out the calibration.
Like @knyg said, if you start seeing higher numbers then I'd be concerned, especially if they ramp up on a pull. If they show up and go back down to 0 you should be fine. Let's see what the more experienced and knowledgeable here say.
Like @knyg said, if you start seeing higher numbers then I'd be concerned, especially if they ramp up on a pull. If they show up and go back down to 0 you should be fine. Let's see what the more experienced and knowledgeable here say.
Any research on this exact topic show 1.4 as pretty normal.
Pretty common, it's happening when you whack the throttle open.
I'd try running better fuel.
I also got this today..while just cruising on the highway.
91 is the only thing available too me unfortunately. Should I just unmarry the AP and wait until I get my etune done?
Perhaps a different station or try the ACN91 map
I noticed this on the COBB website:I'd try running better fuel.
The key when analyzing data logs is to keep in mind that the knock detection systems on these cars are not overly sophisticated and can report knock events when no knock has occurred. This is fairly typical at lower load or with bigger throttle changes. Also, some occasional small corrections can be normal and do not necessarily indicate a problem. Some general things that we look for that may indicate that a car has a knock issue to be addressed (based on logging)(Non-DIT):
1. Feedback knock correction or Fine knock learning -4.2 or worse at low loads (i.e. cruise/low throttle situations).
So since mine is at -2.8 at the lowest should I not be overly concerned about it? Also, I will try a different gas station as well.
FKL isn't bad, FBK can be bad if it's bad enough.
-1.4 is nothing to be concerned of in either regard.
-2.8 isn't horrible for FKL but can be bad for FBK if it is occurring regularly.
Since you are in Canada, we are/were in the same boat.
On Cobb I fuelled my car exclusively on Petro Ultra 94, as I found that 91 never quite cut it.
I'd be cruising along, literally on cruise, going like 120, and the 'bam' FBK of -2.8 or higher.
Still a very slight/partial throttle but it bothered me.
For that reason I don't use anything but Petro 94, and my tuner suggested it before I even said anything when I was booking my pro tune.
They CAN pro tune for 91, but with the 94 the ceiling is just higher.
If you are stuck with 91, stick to Shell 91 and also do #2:
Second, I ran the 91 OCT ACN tune.
The 91 oct tune seemed 'fine' on the 94 octane gas, but the ACN tune is just a hair safer.
Less knock.
After I got my pro tune the occurrence of both FKL and FBK dropped significantly.
Our gas in Canada just sucks!
I suggest going with the ACN tune for now (I ran it for 2 years) and then if you decide to mod further, go with a pro tune.
A pro tune tunes for your car, with the actual gas you will be using.
It can be a lot more 'exact' to avoid knock issues while also optimizing the tables for more power.
-1.4 is nothing to be concerned of in either regard.
-2.8 isn't horrible for FKL but can be bad for FBK if it is occurring regularly.
Since you are in Canada, we are/were in the same boat.
On Cobb I fuelled my car exclusively on Petro Ultra 94, as I found that 91 never quite cut it.
I'd be cruising along, literally on cruise, going like 120, and the 'bam' FBK of -2.8 or higher.
Still a very slight/partial throttle but it bothered me.
For that reason I don't use anything but Petro 94, and my tuner suggested it before I even said anything when I was booking my pro tune.
They CAN pro tune for 91, but with the 94 the ceiling is just higher.
If you are stuck with 91, stick to Shell 91 and also do #2:
Second, I ran the 91 OCT ACN tune.
The 91 oct tune seemed 'fine' on the 94 octane gas, but the ACN tune is just a hair safer.
Less knock.
After I got my pro tune the occurrence of both FKL and FBK dropped significantly.
Our gas in Canada just sucks!
I suggest going with the ACN tune for now (I ran it for 2 years) and then if you decide to mod further, go with a pro tune.
A pro tune tunes for your car, with the actual gas you will be using.
It can be a lot more 'exact' to avoid knock issues while also optimizing the tables for more power.
Also don't switch back to the OEM map, as the knock was still happening then, you just didn't know about it.
Go with the 91 OCT ACN map, as this is the safest option short of a pro tune.
Go with the 91 OCT ACN map, as this is the safest option short of a pro tune.
I'll try the suggested 91 ACN by you and Josh. Unfortunately 91 is all that's available to me in my shitty area. I am also a minimum 8 hours from a tuner so not a chance will that be happening. I am installing my CBE and turbo downpipe for stage 2 on Saturday and then I am going to have Bren tuning do an e-tune for me. Also, yes our gas really does suck heh..FKL isn't bad, FBK can be bad if it's bad enough.
-1.4 is nothing to be concerned of in either regard.
-2.8 isn't horrible for FKL but can be bad for FBK if it is occurring regularly.
Since you are in Canada, we are/were in the same boat.
On Cobb I fuelled my car exclusively on Petro Ultra 94, as I found that 91 never quite cut it.
I'd be cruising along, literally on cruise, going like 120, and the 'bam' FBK of -2.8 or higher.
Still a very slight/partial throttle but it bothered me.
For that reason I don't use anything but Petro 94, and my tuner suggested it before I even said anything when I was booking my pro tune.
They CAN pro tune for 91, but with the 94 the ceiling is just higher.
If you are stuck with 91, stick to Shell 91 and also do #2:
Second, I ran the 91 OCT ACN tune.
The 91 oct tune seemed 'fine' on the 94 octane gas, but the ACN tune is just a hair safer.
Less knock.
After I got my pro tune the occurrence of both FKL and FBK dropped significantly.
Our gas in Canada just sucks!
I suggest going with the ACN tune for now (I ran it for 2 years) and then if you decide to mod further, go with a pro tune.
A pro tune tunes for your car, with the actual gas you will be using.
It can be a lot more 'exact' to avoid knock issues while also optimizing the tables for more power.
Yes ACN is the best you can do for now.
Otherwise, an e-tune is pretty much a pro tune.
Sure the tuner isn’t there with the car to hear and see what’s going on, but the numbers are the numbers and they’ll still dial you in for your setup with your gas.
For your tune, make sure you have a tank of the gas you’d typically use so they can dial it right.
Shell is some of the better 91 but if u don’t usually go to Shell then tuning on their gas is silly cause when you put some Esso in the ethanol is different (and the gas arguably isn’t as good) so u risk some slight knock.
Either way a custom tune on local 91 will be better all the way but just try to fill up with your preferred
Otherwise, an e-tune is pretty much a pro tune.
Sure the tuner isn’t there with the car to hear and see what’s going on, but the numbers are the numbers and they’ll still dial you in for your setup with your gas.
For your tune, make sure you have a tank of the gas you’d typically use so they can dial it right.
Shell is some of the better 91 but if u don’t usually go to Shell then tuning on their gas is silly cause when you put some Esso in the ethanol is different (and the gas arguably isn’t as good) so u risk some slight knock.
Either way a custom tune on local 91 will be better all the way but just try to fill up with your preferred
Happy to e-tune your car and optimize it for your available fuel.
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