NefMoto

So started my tune not so long ago and feel like its going OK so far. Now I've increased my boost significantly it looks like my car is over-correcting when I peak, to the point where it dips under requested, comes back up again and overshoots. I've done a bit of reading and tried to make sure I'm logging the correct variables to help solve this.

spec is:

k03s 1.8t
2.5" cooler pipework and fmic
4bar fpr 317cc injectors
2.5" exhaust system no cats
intake pipe etc etc

From the wiki i can see that it says if ldimxa adaptions are happening (there are some) I will probably need to look at changing KFLDIMX and LDIATA. I'm thinking that the PID being stock is the reason for spec boost not meeting requested though I could do with some more expert opinions  ;)

I'm hoping its not related to KFMIOP or KFMIRL being tuned incorrectly. From the variables I am able to log i can see that mifa_w, misol_w, migs_w and miist_w aren't exceeding miszul_w and i have no crazy timing oscillations that would make me suspect its the torque model causing the problem though i may well be wrong.

Hoping I can get some advice on this to move me forward. Another problem i have is that i cant seem to line up/define KFLDIMX correctly in my file (032TL ecu) when comparing to a 032HN the hPa axis doesnt come out right as pictured, can anyone offer advice on finding this or even possibly help me find it as I think even if this isn't my problem at the moment it'll need looking at soon. In the meantime i shall continue to study the wiki and probably get on youtube to watch some videos on PID control.

thanks in advance,

Dave

I would start to make boost request more "stable" at 3000-4000rpm and reduce imx a little at that rpm range

Thanks for the reply, I've attached a picture of LDRXN as it is in my file, around 3500-4000rpm requested boost seems to take a dip but I'm not sure why since my LDRXN doesnt look like it would have a dip at that point. At this moment I'm unable to properly define KFLDIMX  :( though I've defined LDIATA

So you were able to copy-paste KFLDRL but not KFLDIMX? You should spend A LOT more time on learning how to find the maps by yourself before you start trying to "tune" the car without even having properly-defined maps for it.

When you say copy and paste how do you mean? I've been defining maps the only way i know how to which is to compare windows in winols, then when i find a match I transfer the map structure. As I've moved along I realised I need more maps so have kind of been adding them as i go along. I'm not sure why i was able to find KFLDRL but am struggling to properly find KFLDIMX, Is there a better way i can learn for finding maps? The axis data just doesn't look right at all lol

The .kp file i uploaded is all my work, albeit the file could be better i have defined a fair amount already. I have been unable to find a damos for my ECU. I really would appreciate some advice on how to find the maps correctly, as at the moment I'm a bit stuck lol

KFLDIMX:

0x1EA4E 16bit, factor: 0.005 * X

ROW: 0x15D42 16bit, 8 rows, unit hPa, factor: 0.039063 * X
COLUMNS: 0x1303A 16bit, 16 columns, unit RPMs, factor: 0.25 * X

Thank you very much! my axis now looks correct  ;D may I ask how you managed to find that? I'd like to learn how to find them rather than just having to do it by comparing.

Thanks again, that was a big help to me.

Hello Dave,
Reverses the axes, so it will look better

It has taken me many hours to find the maps, comparing with the 032HN and 018CB defined files

Since for our cars Ibiza 6L FR 1.8T (032QN), Ibiza cupra 6L 1.8T (032RP) & Polo gti 9N3 1.8T (032TL) there is very little information and the definitions are almost the same between them

Will do, i just did that so i could squeeze it on the screen!  ;D

Yeah there is little info on these ECU's. I had found all the maps I needed just by comparing up until now. Maybe i should have just used a HN or HJ file as i think they may be able to be cross-flashed and there are some good damos around for those lol.

Have you successfully tuned KFLDIMX for your car?

I'm going to do a lot of reading and then try to sort out my boost pressure overshoot.

First raise the limits in KFDLULS

To start tuning KFLDIMX,
Set the last row (980 hPa) all to 95
Add +4 or +5 offset to rows (750 & 900hPa) in range 2250-5500rpm
and tune KFLDRL & others...

Thanks! I think i have been getting a little confused and concentrating too much on KFLDIMX.

Should I make changes to KFDLULS since as the moment I have not had any throttle cut from boost deviation? I think standard values are 400mBar and from my logs the max deviation i can see is around 100mBar.

I'm a bit confused as to why we make changes to KFLDIMX so i need to do more reading on that.  ??? ???

As for KFLDRL, as an example is this the map i would use to correct the overshoot, since the result of the PID goes to KFLDRL and then dictates the n75 duty cycle - would I find the part in KFLDRL that lines up with the rpm range where i see the overshoot and slightly reduce the duty cycle to cure it. Is this the correct way to tune it?

don't touch KFDLULS


No.

My bad - Thanks for clearing that up though.

KFDLULS wont get touched, I'm not getting any pos or neg deviations (yet) - and if i was then increasing these limits wouldnt be the answer to those problems right?  :P

Looking at my I adaptions I can see there is some, from your wiki it states if they're downwards then I'm overboosting. I'm now just not sure what this info means in terms of making changes to KFLDIMX and LDIATA

correct!


You should probably review how a PID works, and the relation between over shoot, under shoot, and PID integrator wind up.

I don't have the patience right now to give a lesson on PIDs :(

No doubt, it seems like a big subject and a complicated one to cover easily. I think youtube may be my go to place for a half decent noob explanation to try and fully understand what is happening with my boost control.

Slowly but surely moving forward with this so thanks for pointing me in the right direction. It makes it a whole load easier when you at least know what not to do - and also what I need to know/go read up on.  :D

http://s4wiki.com/wiki/Tuning#Boost_PID
http://nefariousmotorsports.com/forum/index.php?topic=6695.msg75036#msg75036

kfldimx axis defined incorrectly, its started with 250hpa
you should not touching values at factory boost levels when you running stock wg
remove a few lower axis values (1 or 2), move factory map data according to this and add new boost levels with a new values.
like this

250 350 500 900 1100 ->  250 500 900 1100 1300


just slightly rise them. no rocket science when tweaking stock turbos

correct, the axis are bad defined, start at 15D44
with values: 250 300 330 470 750 900 980 1100

Thanks guys - Axis changed and then shifted along one so it now starts at 300 and ends at 1300 (1300 hPa being around 19psi right?)

I took some more logs this evening and something doesn't look right with miist_w - It can also be seen on my actual engine load, it stays flat for a good while and then there's a fairly big dip and I'm not sure whats causing it. I'm not getting any timing oscillations as i would expect to see if it was torque monitoring. I believe miist_w t be the output of KFMIOP corrected by lambda and ignition angle efficiency?

I have modified IOP axis to suit my new max specified load in LDRXN, I have also allowed more load via KFMIRL. Maybe this means i need to tweek my IOP? I've read a fair bit of conflicting info regarding IOP, some people seem to change the values in the table as well as the load axis, and I've seen some people say to the values in the table stock and just increase the load axis. I personally changed the last 3 load axis values and the values in the table for those load axis values to line up with the higher values in IRL. Kind of gone off topic but cant imagine it'll be helping if my torque model isn't right.

4th gear log attached

You're requesting way too much boost up top for your hardware.

Look at your WGDC and lde.

Should really reduce LDRXN higher up then since I'll never be able to reach those. I can see from the PID I adaptions they're rising so that means underboost - which is expected as my requested is literally unreachable for my hardware that high up in the rev range. Will reduce this so my wastegate DC isn't sat at 95% for ages lol.

Do you think miist_w looks right or is there probably something up. That big drop in my engine load just doesn't look nice  :-\

Got some more logs with a slightly modified LDRXN (requesting less at top end of the revs) KFLDIMX axis has been shifted so my top value is 1300mBar also. For some reason I'm seeing a dip in my requested boost but not really sure why this is. VVT is inactive so it shouldn't be that causing it. KFLDHBN is at 3 across the board so that wont be limiting it. KFTARX is stock however my intake temps didn't get above 15 deg c.

No torque intervention either as I switched it off to rule it out being that in this log so im not sure what else could be causing it.

Log ARMD

I've removed ARMD as it's always caused issues even with low levels of boost so I'm not sure what could be causing it. I will double check but I'm 99.9% sure I've already removed it.

I see zero torque intervention or armd. Neither interfere with req boost, regardless. Anyway, that last log looks really good.

I wouldn't disable torque intervention, nor would I disable armd entirely.

req boost changes with intake temp even with flat KFTARX. I wouldn't worry about it. In theory, there is a (not flat) KFTARX that can 1:1 counteract the load->boost dependency on intake temp, but it would take a bit of effort to calculate.

Thanks Nyet - I will re activate TM soon, and i'll numb ARMD rather than removing totally. I just disabled it as a way to determine if that was or wasn't the problem.

I'm thinking i either have an issue with KFLDIMX or my calibration of IOP and IRL since I get a weird surging sometimes at part throttle.

Other than that I'm feeling happy so far, the dip in the boost is a bit annoying as i can feel it when at WOT, its not severe but it would be nice to have a smoother curve. Does KFLDIMX affect the requested boost at all?

Glad I have no CF's though, means there's more to come :P

I may try to re tune IOP and IRL by doing some linear interpolation in excel, just because from what i remember with my LDRXN I was quite close to miszul with the LDRXN I have, maybe that would sort the surging.

I'd really like to add some more variables to log, ones that didn't come up automatically though i have no idea how to add them - i know you have a list of extras on your github ;D

You'll have to learn how to disassemble or find somebody willing to locate those for your file for you.

Maybe one day  :-[ haha. I forgot to shift the map data when I changed the KFLDIMX axis. At the moment I get some part throttle boost surging around 3k rpm between 5-10psi on the gauge. Hoping when I shift the map data it'll sort itself out

Part throttle surging usually isn't related to IMX.

Depending on your setup, the only part throttle surge that is map related is if your wgs are significantly tighter than stock, and the ECU doesn't know to use throttle for part throttle at boost higher than stock wg cracking.

If, on the other hand you are getting surging at WOT, it is something obvious like too much IMX too low.

Log.

Thanks for being so helpful - it's probably frustrating as hell haha. I'm literally about to go try log it and see if I can capture it in the act haha

Roads were soggy but managed to catch it, logs suggest my requested engine load going up and down as well. Throttle plate angle seems to be at 100% but the boost was fluctuating with n75 showing similar trend. Can't see any CF's either and miszul not exceeded because TIV is off on this file. I have another file exactly the same but with TIV active.

I don't understand what you are trying to do there... the requested boost is barely anything.

The problem doesnt seem to occur when doing a full WOT 3rd gear pull like I usually would for logging. The best way I can explain when it happens is if I accelerate up to 3000rpm off boost, then put my foot down about half way and hold it in that position - then the boost pressure seems to fluctuate fairly quickly between about 5 and 10psi. I managed to capture it in the log above  ???

Yes, that is part throttle problems for wg that are different from stock.

Does the wg have stock cracking pressure?

Yeah wastegate is stock and cracking pressure should be stock since no one has ever adjusted the wastegate arm - weird!

Does the car behave that way part throttle with stock PID?

With stock turbos/wgs you shouldn't be touching ANY PID PARAMETERS except for IMX.

Was literally just swapping the IMX axis back to stock as that was the only thing PID related i had changed. I swapped it back and no fluctuations!  :D

stock axis is 250, 300, 330, 470, 750, 900, 980, 1100. I had changed it to 300, 330, 470, 750, 900, 980, 1100, 1300. (all of the values in the table were stock, just shifted the axis to try and allow for the extra boost I'm running over stock)

Would you recommend keeping the IMX axis stock? or should I be changing only a couple of the larger axis values rather than shifting the whole thing?

Nothing should be done without a good reason to based on logs.

From what I see in the logs it seems to control quite well, no massive overshoot or anything. My only gripe is that my requested boost has a large dip at around 3500RPM that you can actually feel at WOT. I was hoping to smooth that so there was a no dip as such - IMX shouldn't be what I look at changing to correct that should it? Since requested boost shows the same dip as actual. I'd be right to look at changing IMX if actual wasn't meeting requested?

In the wiki it says specified boost is calculated from requested load, and that specifically at WOT the boost profile should follow LDRXN, though it isn't following in my case and KFLDHBN isn't the limiting factor.

Is it possible that the ecu is reducing requested boost at that point because it doesn't need any more boost to reach the desired engine load at those rpm's?

No. One more time: IMX has nothing to do with requested boost.


No. Why would adjusting IMX change requested boost?



No. That isn't at all what the wiki says.


No. At this point you are going to have to read the req load to boost description again, from top to bottom, and understand every single step along the way.

Sorry. The way I wrote my question/reply made it come across different to how I intended. I was looking for clarification that I was correct in thinking IMX was not the place I needed to be messing with just yet since that wont change requested boost and that IMX wouldn't change requested boost.

Re-visited IOP and IRL and logged it, seems to follow better than before. Some I adaptions higher in the revs, and small over shoot in boost that would be good to sort.

That actually looks pretty good.. i'd back off requested boost more up top so the wgdc doesn't ride 95 as long though.

You want a bit of leeway or you may throw a code if you dont meet requested boost long enough even at 95 dc.

You're also out of injector at the top, so I think you need to pull back boost anyway; you have zero egt or timing safety if you should need more fuel.

Will pull it back with LDRXN later today - i think im at about 95% duty on the injectors (317cc @3 BAR) running 4bar fpr. Now I can see how close I am to maxing them I think a worthwhile upgrade would be the 380cc ones from the 1.8t 225bhp engine, that should give me some headroom.

For now though I'll pull it back a tad and make sure wg Isn't maxed out for too long!

I'd like to tune it to get the most out of the hardware, then the intention is to install WMI (pwm controlled). That can wait though especially as the tune isnt anywhere near finished lol  ;D

DC has nothing to do with it, the boost request is fine, KFDLULS has much more leeway than that.

Not sure whether you guys deem it worthwhile but I'm thinking of making some very small adjustments to the derivative function of the PID to try and get the little overshoot (when actual meets requested) in check. the s4 wiki leads me to believe i'll need to slightly raise the values I  KFLDRQ2 to cure it.

One axis I have RPM and the other is hPa which from what I've read is 'ground pressure' which goes from 100 -700hPa. Am I right in saying I should only need to tweak the values for the 700hPa row at the say 2 rpm figures where I am seeing the overshoot. Finally, is there a quick way to calculate how much I should increase them by. I guess i could bump them up a small amount and do lots of logging and revisions but if theres another way that'll mean i only have to do half the amount of revisions that would be good to know  :P

The wiki is kind of wrong. You should be able to fix 99% of over/undershoot with IMX. I have edited it accordingly.

Also, the pressure input to Q1/Q2/Q3 is always lde, not "ground pressure", as is also noted in the Tuning page.

IMX seemed good for sorting undershoot, I bumped up the values ever so slightly at certain points and got the boost closer to requested. However when i tried dropping the values around the area of overshoot it didn't seem to do much but shift the overshoot along in the rev range.

I'll have another go though, maybe I didn't reduce the values in IMX enough to see a proper change.

You may get undershoot followed by overshoot... At that point tweaking q2 might be needed... Increase imx until just about all undershoot is gone, then change q2. Also, because of the way pids work, a bit of overshoot is inevitable.

I've made some changes to IMX and removed a fair bit of the undershoot and feel fairly happy now - though i need to drop ldrxn a tad maybe since I think even with 95% DC i'll not hit the requested boost higher up in the rev range. It's not severely out though.

I'm wondering if its maybe time for me to adjust the differential term of the PID to tame the overshoot and ripple (i think that's what the subsequent undershoot is called) I've attached a log and some pictures lde included in the log.

So if tweaking the PID may cure it, I'd be needing to increase some values in KFLDRQ2. Using lde to help me determine which row or rows i need to change values in, as well as rpm - would I be right making these changes at the rpm's just before the overshoot occurs rather than at the RPM of overshoot as presumably that's too late for me to see the desired changes occur?

In dummy terms do I need to reduce the speed at which I am approaching my set-point (desired boost) the closer I get to it, to reduce my error? and that could be achieved by increasing the D term? Please excuse my lack of correct terminology, I'm just trying to get a half decent grasp of why I might tweak KFLDRQ2 rather than just doing it because.

log attached, the IMX i'm currently using and a screen shot of boost and lde.

I max is still too high.

and perhaps increase requested from 2000 rpm to 3000 to make things happier

agreed.

Thanks Nyet for your previous comment, I pulled a fair amount out of IMX and now have no overshoot. Got a slight dip but maybe that'll be fixed if I increase requested in that area?

If I bump up IMX a tad where i see the dip and increase requested hopefully i'll end up with a fairly smooth looking line.

I don't like that your request is so close to actual during spool.

Can you explain why? For learning purposes

I've since increased req on spool as you suggested, why did you suggest this? was it to stop any intervention if I came too close to actual on spool?

I've also noticed in all my logs that IMAX doesn't follow anywhere near WGDC, this doesn't seem right  ???

To make sure PID is stable during spool - P should be big enough to provide 95% wgdc, and I should have had had enough time for full windup so it is riding IMX before peak boost.


See above regarding integrator windup. Also don't forget there are other terms (P and D) and the LDRL table as well.

Also, this isn't really the place for me to explain integrator windup; it would take me forever, and I don't know your math background. You'll need to do your own learning regarding PIDs.

As an exercise, though, under what conditions would you expect wgdc to EXACTLY follow IMX?

Would IMX be the same as WGDC on spool until just before peak boost? since you'd want to be at 95% WGDC on spool up until the point where requested meets actual and it then needs to control to become in line with requested?

Would it also be the case at 'steady state' that you'd like WGDC to be in line with IMX?

Hopefully i'm not way off the mark with what I said there though I fear I'm likely wrong  :-\

Not even close :(

I am not sure how much time i want to spend here :(

Anyway:

P result + I result + D result goes into ldrl, and comes out as wgdc.

I result is limited by IMX if the integrator is completely wound up.

The rest of the answer to my quiz follows from that reasoning, but I fear it would take me way too long to get you to understand PIDs. You really need to do some independent learning first. It would take me way too much work to teach you everything you need to know.

Thanks nyet. I think I may have discovered the error in my ways. I'd been setting a smooth LDRXN and getting too tied up with making it look smooth when really that was my problem, I've now messed with LDRXN and upped it where i had the dip in requested boost between 3 and 4k which IMO made it really hard to control, and I could feel the drop in torque when driving which wasn't nice.

Now my LDRXN is changed my requested boost looks a lot better and i hope will be easier for me to control without any fluctuations in boost.

Pulling a fair amount from IMX did result in a massively reduced overshoot, i hope with my fixed LDRXN and nicer desired boost that with some mods to IMX i'll have it exactly how I want it. Will update when I get it sorted as it might save some other noobs some time  ;D

So, this is where I'm at after lowering IMX quite a lot, it's looking a lot better from an overshoot perspective imo. Though I now have ripples can someone please confirm if this is because I've lowered IMX too much for these areas? or should i be looking elsewhere to try and rectify this?

Its FAR from perfect but I think I'm beginning to make some progress with this.

yea a bit too low.

Cheers for the quick reply. Adjust then back out onto the road  :P

You'll never be able to tune out all of the wobble.

Is it realistic for be to be able to get it better than that? I'd like to make those fluctuations a little better but kind of stuck now. I've started upping IMX between say 3k and 4k rpm's a little at a time with no real success. Seems from my logs that just after it peaks my IMX is too low for it to maintain requested, so WGDC keeps spiking to try and get to requested even though the IMX is much lower than required.  :-\

Yes it is.

Notice how your I-MAX is smooth, but your WGDC is all over the place?  What does your KFLDRL look like?  Pay less attention to your actual boost, and pay more attention to the WGDC.  You want to make that smooth instead of jagged like it is now, and the boost will even out as well.

You could also look at boost pid trims to see how the ECU is trying to compensate, and apply those trim adjustments to DIMX, in the same manner that you would tune KRKTE based on partial LTFTs.

Thanks for the help, my KFLDRL is totally stock at the moment, I've added a picture of how it looks also a picture of my current IMX and a log.

I've been logging the boost PID I correction factors, I take it if I see these rising that suggests I should increase IMX in those areas?

At the moment I guess my IMX is way too low to deliver the desired boost pressure, I had spent a long time trying to reduce any overshoot by dropping it but it seems I've dropped it far too much.

Yes, positive trims = increase, negative = decrease.  Look at STLDIA1-4 to determine the rpm ranges.  Look at the S4 wiki's I-Regulation adaptation section for more details on this

At first, ignore the overshoot, and try to get boost stable with DIMX.  Once you are good, increase Q2 in the areas needed to prevent overshoot on ramp up.   To aid in keeping boost a little more stable on initial ramp up, you could slightly decrease values in the 95% column from ~3,000 to ~4,500rpm.

Your request should be flat during spool, not rising.

Did you do anything with D term (Q2)?  Looks like too much. 

I agree, you can do just about everything with imx

Thanks SB_GLI , I'll put that into practise soon. I think I'll raise my IMX up a fair bit to get me closer to desired boost ignoring the overshoot so my WGDC isn't flapping around all over the place. Then I'll report back hopefully with some decent results.

I have not yet touched any of the PID maps, the only thing I've messed with is IMX up until now. I'm just feeling like whatever I've done so far hasn't really got me much closer to getting it right lol however I never wanted to mess with the PID maps if it could all be sorted with IMX. I've done that many revisions with IMX at different settings and can't seem to get it right  :(


Nyet, by this do you mean i should be making some changes to my LDRXN lifting it way above actual boost on spool to the point where on my logs my requested boost looks like a horizontal line (obviously then tapering down as revs increase and turbo can't keep up)

Yes. I even explained why a while back.

Made some adjustments to IMX but it's still not right. Seems like whatever I do with IMX I end up with that dip in boost around 3500rpm. I've tweaked IMX so many times and can never get it anywhere near being right

I've tried to make the boost request flat on spool as nyet suggested, not sure if what I've done is actually what is required or not though.

Is this dip in boost around 3500rpm the PID almost over correcting the over shoot? or is it because my IMX is too low in that area?
As if its the PID correcting the overshoot then I should decrease IMX to stop the overshoot, but if its because imx is too low then I guess I need to increase those areas of IMX?

Also I don't seem to be getting that many boost PID corrections in the are where I'm having all the problems  :-\

Your request looks good... going to be hard to tune out the rest.

Might need to adjust Q2... can you flatten out IMX a bit (remove that dip between 2500 and 3000) so we can rule it out?

You'll get some overshoot, but that will tell us whether IMX should come up as a whole and if you need more Q2

You won't get ANY i max trim corrections at this level of fine tuning.

Don't worry, you are getting close now.

Cheers, that makes me feel a lot better haha seriously felt like i was going round in circles!

Literally just got back in from doing some logging, by chance I just so happened to have been messing with that exact area and have flattened it to 70, prev was 68 probably giving that dip in imx between 2500 and 3000.

I presume I'm going to need to lift the values a bit more than they are set at at the moment though, if so i'll make some adjustments and log tomorrow.

Looking good, dont worry about small wiggles, you're looking to cure big over/undershoots.

Flatten/simplify IMX more and it will help tuning q2. Find a nice flat setting where over/undershoot is about equal, and we can move on from there.

Also, you're maxed out up top, you need to taper LDRXN more.

i'd start with drawing a straight line from 2250 to 4500 from 80 to 100, and flat 100 all the way to redline from there.

Im on this topic like a hawk.  ;D
 I'm dealing with the same PID headache at the moment :)

Bottom line: if your IMX has more than 2 inflection points you are doing it wrong.

Your obsessed with tuning out overshoot.

It's designed to overshoot, turbos have inertia, watergate ports can only control so much as they transistion from closed to open.

The reason your boost is a bit wappy, it because of pid.

It's trying to make it hit request, then as soon as it hits request it goes wappy. your not letting the boost go over requested for the pid to function correctly and control it down in a smooth manor.

IMO if you let it overshoot a little bit the pid will become happier and things will smooth out to factory like control

Yeah, I think you're expecting it to follow perfectly and that's just not how a PID works. You want it to overshoot.

I'd recommend you watch motec closed loop pid control YouTube video it's very long tho. But you'll then understand why a slight overboost is desirable for pid function.

I'm more bothered about the undershoot that seems to follow the overshoot on ramp, which I can feel when doing a 3rd gear pull. I'm going to flatten IMX as Nyet suggested then hopefully some Q2 changes will improve it a little more. I'm not after perfection, just something that feels better when driving  :P

I'll watch that once I'm home from work for sure!

Just changed the file slightly and flatted out IMX a lot more, then had it increase to 95% beyond 4500rpm. Less points of inflection vs the revision before this one. Not got equal overshoot vs undershoot just yet though.

Altered LDRXN at the top end so req is closer to actual and it looks like it's about right now.

Should I raise IMX up, but keeping the same profile/shape to try and get an equal overshoot vs undershoot?

Yes, you need slightly more IMX @3,500, and maybe a hair more Q2.  Very close.

Potential stupid question here but I set IMX flat at about 80%, this seems to then translate to an actual imax of say 85 on the logs. Is that down to some sort of correction made by the ecu?

Thanks for the reply, it means I've got time to lift it, flash the file and take a few more logs before it gets too late  :P

I've not touched q2 just yet since I'm not sure in what increments I should be increasing it by so felt best to leave it until I knew, and or everyone was suggesting to start tweaking it haha

 LDIATA

 ;D ;D

This looks half decent to me, made some very small changed to Q2 as a last ditch attempt whilst i was out and it seemed to have gone well!

Bingo.

But I'd bring requested boost down above 4500 and ilimit to 100% so 95% isn't ever required (and you aren't riding the ilimit); you want some overhead, otherwise when you ride the i limit the pid Q and P terms will make your dc choppy.

That's the job for tomorrow sorted then :) can now maybe add some timing, kept it pretty low for obvious reasons and nice and rich!

I'll also post some pictures of what I changed, that way someone else can benefit from this thread. Thanks a lot to everyone who contributed to helping me in this thread really appreciate your time! I'm super  happy with how it drives now - Just feels like it's pulling constantly  ;D

Nice thread!

Just one question, do you have the intake resonator installed? Sometimes produces overshoots when it is fully filled, at this moment the pressure returns to the TB housing making a little overshoot.

Interested to see how much you used Q2 to correct the dip

Pics attached as requested, to be honest I don't know if I've done it the right way but hopefully someone else can take a look and tell us if it's ok or not. Pics of stock and tweaked version of q2

I've also attached a recent log, where the problem is still present but no where near as bad, so maybe some more q2 is needed.

I also fitted some 386cc injectors to give me some more headroom/safety which is nice, was running the stock 317cc with a 4 bar fpr so not a massive gain but maybe less strain on the fuel pump because i was able to go back to a 3 bar fpr - that always has to be a bonus surely?

Timing is quite high and it goes very well so far, I realise I'm squeezing the little k03s quite a lot but its a nice challenge to see what I can make it do I feel.

Thought the axis of the Q2 was LDE error?

I've adjusted the lower rows 100-200 with good success

Whoops lol! more understanding needed haha. Ive just set it back to stock and started adjusting for the lower lde axis values, seemed to make a small difference but not perfect yet!

Hi Everyone

I have a question, what can cause that big boost spike 18PSI at peak, and then everything back to normal. This is stock map i only calibrated KRKTE for the bigger injectors...
A4 b7 1.8t BFB with k03S, de-cat.

Should i try to fix that spike with KFLDIMX/ KFLDRL? Or this is a hardware issue?
Also that big spike started happening after i perform full engine decarbonisation, this is the method https://www.youtube.com/watch?v=VBHQHwiQ1Yo

 Thanks.

It's probably only "ok" (I use that term loosely) because the throttle plate is closing from overboost (you didn't log it so I'm just guessing).

Likely you have a torn WG or busted N75.

Nyet, i've tried to disconnect the N75 and it result with no spike nor boost at all (~0.3) bar.
Connected back and spike come again ~1.1bar. So maybe the torn WG is the issue?

But in any case my fuel trims are around 1% so i'm pretty sure that i do not have any leaks.
Also no CEL.

That sounds more like a bad n75

I've had a handful of cars exhibit this behavior with old N75's. Seems the response time slows as they age, which causes the spike.

Issue resolved. Old N75 was the issue, replaced with the brand new revision "E". No more spike and turbo feels much more responsive on low RPM.

Thanks.

Glad you got it sorted! In particular, thanks for keeping us updated.