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Time to identify once and for all the source of my FKC


xt2005bonbon

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Found a relevant post by someone very knowledgeable on RomRaider in this thread.

 

I don't hear it, but have considered looking into a pair of det cans or something. Also, in the past when I have "heard" it, it has shown up in the real time graphs as FBKC. I'm just basing this off of observations over the last 3 years.

 

false or not, it goes away with the addition of timing...this is the puzzling part.

 

Not really, high EGTs will cause knock just as easily as timing that's advanced too far. Advancing the timing drops your EGTs, so if your knock was temperature-based instead of preignition-based, adding timing would reduce it.

 

It's a well-known problem when people bias their base/advance timing maps too heavily on the advance side. If the IAM drops due to a bad cell, the greatly reduced timing across the board can introduce temperature-based knock, dropping IAM even more or pulling out FLKC or FBKC.

 

JSarv also brings a lot of good points, one explains that it's probably not EGT it self for say. Go read the whole thread :).

 

I would stick closer to solidxsnake's timing then mine, my bigger turbo forces me to run 5* less timing then stock VF46 did.

05 LGT 16G 14psi 290whp/30mpg (SOLD)

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

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There is no easy way, this is why after a 1.0g/rev I just subtract 10* of timing and add that 10* in KCA table.

 

You can use Timing Editor v15 for combining them, smoothing them then getting it back into RomRaider. Sadly it only works with Romraider tables, maybe NSFW can add support for generic table pasting like ECU Flash. :)

05 LGT 16G 14psi 290whp/30mpg (SOLD)

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

22 Ascent STOCK

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Just so you all know....

 

I actually changed my mind for the time being. I want to halt everything and have an oil analysis done, as I've always had to add oil to this engine and lately I've had to add more than before (granted I push the car hard).

--I know that I do not have any oil leak (e.g. pass valve cover is not leaking at all--I fixed that and kept an eye on it; no other apparent oil leak).

--I pulled the tmic a couple of weeks ago and I barely see any oil in there (nice and clean).

--The throttle body hose looked fine too.

--PCV valve has barely 30k on it.

--The DP was off a couple of months ago; the exhaust side of the turbo looked nice and dry

--my tail pipes are pretty black but can't see that there are 'wet' per say.

--the engine oil gets black pretty quickly and has a gasoline like smell. My 06 does not do that: oil stays light brown for quite some time and still has an oil smell to it.

 

I am starting to feel like I really have a ringland issue or something. So last night, I went ahead and pulled some of my engine oil and will send it to Blackstone for analysis this morning. We shall see what they say :spin:

 

Engine has 100K btw.

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Might actually be the best idea. Although 100K is barely past puberty for a mid-2000s era engine, turbo or not. I have a suspicion the issues have more to do with the age of the various components, assemblies, sub assemblies. All the heat cycles and seasons do 'wonders' to electronics and to a lesser extent mechanics too.
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I get that tuning is scary, but I really don't understand why you would want to postpone a simple and easily revertible tune change that might actually benefit your motor. Actually I'll go as far as saying, all the symptoms you described are related to a bad tune (for your setup).

 

Eating More Oil - Can be explained by detonation and beating on the car. My car looses (consumes and or leaks) a lot more oil when I'm doing 20-30 WOT pulls while tuning. That's just the nature of the game, driving a car hard will do that, especially a Subaru and especially with 100k+.

 

Tail Pipes being black - Your tune has too much unburnt fuel. This could be from being too rich, or having timing that's too retarded.

 

Engine Oil Gets Black Quickly - Your tune has too much unburnt fuel, which leaks into the crancase. This could be from being too rich, or having timing that's too retarded.

 

This also could be because of how the oil was changed. I always keep the drain plug open and poor new oil in until clear oil comes out. The reason you need to do this is, most oil pans have about a pint of oil reserve that doesn't drain out to prevent dry starting. If you don't displace this dirty oil, it's just going to taint your fresh oil. If your getting your oil changed by a shop, you can forget about them taking this extra step for you.

 

 

I just don't understand this aversion to tuning, you remove the benign tumor before it becomes an issue, not after :lol:

 

 

Just so you all know....

 

I actually changed my mind for the time being. I want to halt everything and have an oil analysis done, as I've always had to add oil to this engine and lately I've had to add more than before (granted I push the car hard).

--I know that I do not have any oil leak (e.g. pass valve cover is not leaking at all--I fixed that and kept an eye on it; no other apparent oil leak).

--I pulled the tmic a couple of weeks ago and I barely see any oil in there (nice and clean).

--The throttle body hose looked fine too.

--PCV valve has barely 30k on it.

--The DP was off a couple of months ago; the exhaust side of the turbo looked nice and dry

--my tail pipes are pretty black but can't see that there are 'wet' per say.

--the engine oil gets black pretty quickly and has a gasoline like smell. My 06 does not do that: oil stays light brown for quite some time and still has an oil smell to it.

 

I am starting to feel like I really have a ringland issue or something. So last night, I went ahead and pulled some of my engine oil and will send it to Blackstone for analysis this morning. We shall see what they say :spin:

 

Engine has 100K btw.

05 LGT 16G 14psi 290whp/30mpg (SOLD)

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

22 Ascent STOCK

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I get that tuning is scary, but I really don't understand why you would want to postpone a simple and easily revertible tune change that might actually benefit your motor. Actually I'll go as far as saying, all the symptoms you described are related to a bad tune (for your setup).

 

Eating More Oil - Can be explained by detonation and beating on the car. My car looses (consumes and or leaks) a lot more oil when I'm doing 20-30 WOT pulls while tuning. That's just the nature of the game, driving a car hard will do that, especially a Subaru and especially with 100k+.

 

Tail Pipes being black - Your tune has too much unburnt fuel. This could be from being too rich, or having timing that's too retarded.

 

Engine Oil Gets Black Quickly - Your tune has too much unburnt fuel, which leaks into the crancase. This could be from being too rich, or having timing that's too retarded.

 

This also could be because of how the oil was changed. I always keep the drain plug open and poor new oil in until clear oil comes out. The reason you need to do this is, most oil pans have about a pint of oil reserve that doesn't drain out to prevent dry starting. If you don't displace this dirty oil, it's just going to taint your fresh oil. If your getting your oil changed by a shop, you can forget about them taking this extra step for you.

 

 

I just don't understand this aversion to tuning, you remove the benign tumor before it becomes an issue, not after :lol:

 

I knew you were going to school me :lol:. Hard to explain but I did spend some time last night looking at my base timing table, yours, my stock one, looked at logs I recorded yesterday, and also looked at old revs from 4 years ago. And I saw that there were more timing in these cells (around 30 deg) and yet issue was there. Also, I recall when I started to learn about how to use romraider and stuff back in 2012, I was already seeing that -6 deg pulled. And that was I believe still at stage 0.

 

So I just feel it is a lost cause at the moment and we may end up chasing our tail. Of course, I surely hope I am completely wrong and it could be a stupid thing such as a rattling engine mount or something.

 

If you want, I would let you modify the tune. I can give you a few $$ if you want. And I won't blame you if it explodes :spin:. It's just hard to sit down, concentrate late at night and have kids running around and stuff you know. :lol:

 

 

On the oil burning issue though: I push the 06 pretty hard too. That's my DD and she definitely does not burn as much oil. And as I said, its oil has a clearly lighter color than the 05 for the same mileage on the oil (edit: although you have a point about the unburned fuel that may end up in the oil for the 05). She has 160K btw and runs very well. Also, I do change the oil myself on both cars, but never thought about your tip on letting the drain open while pouring fresh oil. Good tip.

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Of course I'm gonna school you! :-). Don't worry about compensation, I just don't wan't another dead Subaru.

 

Since you don't have a wideband I won't touch any heavier loads. But I did clean up reduce/increase and smooth out your daily driving regions. You should have the updated tune in your email.

 

Here is how much timing I removed and added. Even with 14* removal in some areas, it's still 5-10* more then stock :spin:

http://legacygt.com/forums/attachment.php?attachmentid=262837&stc=1&d=1520436794

 

 

Keep us posted on overall driveability and if the knock is still around.

657263171_BaseTimignUpdate.png.fda4f7fefda578c6b43a3983cb54db86.png

05 LGT 16G 14psi 290whp/30mpg (SOLD)

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

22 Ascent STOCK

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You're the man. I will perform these changes and will report.

 

At least, I can also report that I am still getting that knock (albeit it peaked at -3.87 'only') with the engine cover off. Wanted to rule that out since it appeared to be loose.

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xt2005bonbon whats the EGR setup like on the car?

Ever been cleaned or replaced?

 

Can you add EGR step/s to the params you log and see if you get a correlation between higher EGR step values and the FKC you're seeing or at least if you see more FKC pulling timing when EGR steps go up?

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Oki but is the EGR valve still functional and dumping hot EGs into your intake manifold when doing its thing or?

 

Not sure if the resistor would prevent EGR step SSM logging via Kline or CAN... in theory even if the EGR solenoid is unplugged, EGR subassembly removed and various DTCs disabled, unless the EGR table in the tune is zero'ed out, the ECU would still attempt to command a particular EGR step value as goverened by that table.

 

If actually still functional, we'd know how wide open and for how long the EGR valve was open at the RPM and Load coordinates that might just coincide with your higher FKC or FLKC or both.

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Alright,

 

uploaded the revised tune; went to the gym and did 15 logs :spin:! I briefly went through each one and am only attaching the ones with the famous -5.98 FKC. So yeah it is still showing up. Thinking outloud here:

-- Unless I am mistaken, it looks like most of these occured in open loop. But a few seconds before, it was in closed loop. So I wonder if the transition from close to open loop has anything to do with it.

-- In some instances, you will see that it is running lean during these knock events. As a side note, most of my LTFT are positive and on the high side. After the drive, I checked for vaccum leaks using the simple test (where you blow through the bpv hose while blocking the intake hose). It really felt like 0 leaks. In any case, I wonder if we need to address these positive fuel trims before doing further fixes to the FKC issues. I am still running lean in open loop with a fairly light load.

-- I was not able to hear any audible knocks when these occured.

 

These are my thoughts so far.

 

 

Side note: I JUST realized that these four logs have the string 'knock' in the filename while the other 11 logs did not. So essentially, I wasted my time going through each one to check for knocks since BtSsm already does that for you. Freaking awesome tool man.

BtSsm_20180307_195906_knock.csv

BtSsm_20180307_200052_knock.csv

BtSsm_20180307_211311_knock.csv

BtSsm_20180307_211743_knock.csv

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xt2005bonbon whats the EGR setup like on the car?

Ever been cleaned or replaced?

 

Can you add EGR step/s to the params you log and see if you get a correlation between higher EGR step values and the FKC you're seeing or at least if you see more FKC pulling timing when EGR steps go up?

 

USDM 2005-2014 EJ255's don't actually have EGR, they use AVCS to induce overalap & EGR.

05 LGT 16G 14psi 290whp/30mpg (SOLD)

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

22 Ascent STOCK

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Did the car feel any better or worse? More or less responsive?

 

 

First Log's knocks happen at 0.86 load, which could be just noise.

-2.11
RPM: 2499
LOAD: 0.86
AFR: 15.5
PSI: -3.3
IGN: 32.5

-5.98
Load: 0.86
RPM: -5.98
AFR: 15.5
PSI: -3.3
IGN: 28.5

 

The rest of the logs have it at at higher load, which brings more concern.

RPM: 2567
Load: 0.88
AFR: 15.5
PSI: -3.2
IGN: 29

RPM: 2459
Load: 1.19
AFR: 14.7
PSI: 0.7
IGN: 19.5

RPM: 2453
Load: 1.24
AFR: 14.6
PSI: 1.0
IGN: 19.5

 

 

I don't think it would knock that much with leaner AFR's. Thus I'm not convinced they are real just yet.

 

-- Unless I am mistaken, it looks like most of these occured in open loop. But a few seconds before, it was in closed loop. So I wonder if the transition from close to open loop has anything to do with it.

 

That can lead to knock when you floor it, since it will be leaner coming off Closed Loop, but it shouldn't be that big of a deal, especially at med-low loads.

 

-- In some instances, you will see that it is running lean during these knock events. As a side note, most of my LTFT are positive and on the high side. After the drive, I checked for vaccum leaks using the simple test (where you blow through the bpv hose while blocking the intake hose). It really felt like 0 leaks. In any case, I wonder if we need to address these positive fuel trims before doing further fixes to the FKC issues. I am still running lean in open loop with a fairly light load.

 

Your fuel map is pretty weird, might be due to your MAF scales being far from stock. I didn't want to touch anything fueling related, especially since you don't have a wideband. Though factory sensor should be good enough at these low-med loads.

 

At 0.90 g/rev and 2400rpm your fuel map is calling for 14.15 AFR real life is 15.5

At 1.20 g/rev and 2400rpm your fuel map is calling for 13.44 AFR real life is 14.6.

 

Your MAF scales seem way off the fuel map.

 

Can you do some a couple 2nd gear full throttle logs, 2k-redline?

 

 

-- I was not able to hear any audible knocks when these occured.

 

Good good

05 LGT 16G 14psi 290whp/30mpg (SOLD)

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

22 Ascent STOCK

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Did the car feel any better or worse? More or less responsive?

 

It felt OK I guess. No issue really. But then again, I was not trying to push it. I was trying to get to the ~2400 rpm / 0.8-1.2 load range to see if the knock showed up.

 

 

Your fuel map is pretty weird, might be due to your MAF scales being far from stock. I didn't want to touch anything fueling related, especially since you don't have a wideband. Though factory sensor should be good enough at these low-med loads.

 

At 0.90 g/rev and 2400rpm your fuel map is calling for 14.15 AFR real life is 15.5

At 1.20 g/rev and 2400rpm your fuel map is calling for 13.44 AFR real life is 14.6.

 

Your MAF scales seem way off the fuel map.

 

Yeah I saw these lean events and was going to check what the fuel map called for. But you already did :).

As a reminder, I am using a K&N panel filter. So that's probably why the MAF scales were modified. But you know, you are more than welcome to change it. I don't care at this point. If she does not respond well, I can always revert back. My goal in the end is having the cake and eat it too: mpg and power :wub:

 

 

Can you do some a couple 2nd gear full throttle logs, 2k-redline?

 

Yes I can. Although I generally avoid WOT below 2.5-3k. But for testing purposes I could.

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Did the car feel any better or worse? More or less responsive?

 

We drove it more today and, I don't know if it is the 'placebo effect' but I think it felt smoother during very light accelerations. That is another thing we've been disliking with the 05: throttle response. It's just not linear. So it is hard to predict and results in a poor driving experience. Now I understand it is turbocharged and with that vf40, what can you expect. But still...

 

OK. I also did a wot pull with the log attached. It did not knock during the wot session which is great. It actually has not knocked for a long time when pushed. Then again, it did not always reach boost targets (and still does not for the most part---remember my other boost target thread? :) ).

 

Also attaching another log with a knock event in it. This log raises another question: Is it possible to be in an open loop mode while still having some LTF correction applied? If it is the case, then it is possible to be open loop within the load ranges of the LTFTs. I was under the assumption that you can only go in open loop mode pass the highest LTFT upper bound load.

Reason I am asking this is because it appears to me that the beginning of the perceived knock, in that log, occurred during an open loop event as there was 0% fuel correction applied. And yet, you will see that there were some learned fuel corrections during part of the knock. To confirm all of this, I should have been logging the open/closed loop flag.

BtSsm_20180308_145552.csv

BtSsm_20180308_150417_knock.csv

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We drove it more today and, I don't know if it is the 'placebo effect' but I think it felt smoother during very light accelerations. That is another thing we've been disliking with the 05: throttle response. It's just not linear. So it is hard to predict and results in a poor driving experience. Now I understand it is turbocharged and with that vf40, what can you expect. But still...

 

OK. I also did a wot pull with the log attached. It did not knock during the wot session which is great. It actually has not knocked for a long time when pushed. Then again, it did not always reach boost targets (and still does not for the most part---remember my other boost target thread? :) ).

 

Also attaching another log with a knock event in it. This log raises another question: Is it possible to be in an open loop mode while still having some LTF correction applied? If it is the case, then it is possible to be open loop within the load ranges of the LTFTs. I was under the assumption that you can only go in open loop mode pass the highest LTFT upper bound load.

Reason I am asking this is because it appears to me that the beginning of the perceived knock, in that log, occurred during an open loop event as there was 0% fuel correction applied. And yet, you will see that there were some learned fuel corrections during part of the knock. To confirm all of this, I should have been logging the open/closed loop flag.

 

Only the LTFT "D" range will be applied during open loop. From my understanding, this is because it's virtually impossible to be in open-loop when your MAF puts you in the C or lower range; I don't think there's anything stopping the ECU from applying e.g. the "C" LTFT in open-loop, I just don't think you'd ever have that condition unless you modified the map to enter open-loop very early.

 

There's also smoothing when it changes ranges. In this case, it's very clear that your "C" LTFT is around 2.88%, and your "D" LTFT is 0%. When it crossed the threshold (open-loop caused by load crossing over 1g/rev, or MAF over 40g/sec, can't tell which in this case), it transitioned over from the C value to the D value, and this coincided with the single knock event.

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Sorry for the delay, we had our second kid last weekend, so I'v been a little pre-occupied :lol:

We drove it more today and, I don't know if it is the 'placebo effect' but I think it felt smoother during very light accelerations. That is another thing we've been disliking with the 05: throttle response. It's just not linear. So it is hard to predict and results in a poor driving experience. Now I understand it is turbocharged and with that vf40, what can you expect. But still...

 

Smoother is actually what I expected you to say, I smoothed the cruising portion of the timing map WAY out.

 

If I find time again, maybe in 18 years, I'll try to redo your WGDC and AVCS tables :lol:

 

As for the car not feeling linear, part of it is the WGDC tables, another part of it is your AVCS table, last part part of it is DBW table. Smoothness is really hard to tune for without being able to drive the car sadly.

 

 

OK. I also did a wot pull with the log attached. It did not knock during the wot session which is great. It actually has not knocked for a long time when pushed. Then again, it did not always reach boost targets (and still does not for the most part---remember my other boost target thread? :) ).

 

Your timing map is fairly conservative, compared to mine, but you are asking a lot out of a hair blower turbo pushing it to 17psi :lol:.

 

Looks like you did that pull in 3rd gear, because 2nd gear is 110whp/124wtq ;). 3rd is at 239whp/264wtq, with assumed stock tires and weights.

05 LGT 16G 14psi 290whp/30mpg (SOLD)

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

22 Ascent STOCK

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Sorry for the delay, we had our second kid last weekend, so I'v been a little pre-occupied :lol:

 

 

Smoother is actually what I expected you to say, I smoothed the cruising portion of the timing map WAY out.

 

If I find time again, maybe in 18 years, I'll try to redo your WGDC and AVCS tables :lol:

 

As for the car not feeling linear, part of it is the WGDC tables, another part of it is your AVCS table, last part part of it is DBW table. Smoothness is really hard to tune for without being able to drive the car sadly.

 

 

 

 

Your timing map is fairly conservative, compared to mine, but you are asking a lot out of a hair blower turbo pushing it to 17psi :lol:.

 

Looks like you did that pull in 3rd gear, because 2nd gear is 110whp/124wtq ;). 3rd is at 239whp/264wtq, with assumed stock tires and weights.

 

Congratulations! As I've said it before, family first no matter what. So do take care of that little one and your wife as well. No worries.

 

Don't worry about the WGDC table. I will take care of that one. I began working on it a while back in order to achieve boost targets. I am almost there in some areas, but still lacking in others. But I think I know what to do there (keyword: 'think' :lol:).

 

And you are right. I completely forgot you asked to do that pull in 2nd gear. It was in 3rd indeed with two adults, two kids and a bunch of crap in the trunk...

 

Now regarding the knock issue, as I said previously, don't you think we should fix the apparent lean conditions first? If yes, what should be modified (given no actual vaccum leaks)? The MAF scaling?

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You need to tone down the WGDC table at 50% or less throttle, that will make the throttle be less twitchy.

 

No worries, I mainly wanted to see boost vs engine load, 3rd gear is fine but will give you a bigger fine if you get pulled over ;).

 

It's not knocking form lean condition, even 16.0 wont really knock at partial throttle. Now the lean condition when going from closed loop to open loop is related to your MAF scale being off for your setup. You could throw a stock MAF table on (which is honestly sufficient for K&N filter), butttt without a wideband and without retuning the whole map, it's kind of dangerous doing that.

05 LGT 16G 14psi 290whp/30mpg (SOLD)

12 OBP Stock 130whp/27mpg@87 Oct

00 G20t GT28r 10psi 250whp/36mpg

22 Ascent STOCK

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Don't you agree though that whatever you put in the WGDC table below ~5-7psi of boost target don't do squat to the car's behavior? Am I correct in thinking that?

 

So if the knock is not due to open/closed loop transition or lean conditions, what is causing it you think? I know. Hard to figure that one out without driving the car yourself and listening/feeling it...

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