NefMoto

Ive done an engine conversion with a K04 1.8T.
Engine hardware is as found when i purchased engine apart from rebuilding with rods and exhaust valves. 3" DP > 2.5" exhaust.
Wastegate is as i received engine. It was apparently running fine with an APR map but due to not being able to code out the various part that arent needed on that map, I decided to put a BAM 018AH flash onto it and have a go at tuning it myself.

Probem im having is, the boost is way over what is required. And i seem to hit a charge limit if i turn boost up.

I have adjusted fuel to a better profile but boost is always spiking high and staying there. Wastegate duty doesnt seem to be able to control it.

Can someone help diagnose whats going on? Boost leaks checks have been done STFT's are around -0.6%. I've taken some logs with standard LDRXN profile and with N75 disconnected.
You can see the boost just increases upto around 12psi. It seems to point to a stronger wastegate spring but the turbo seems to take longer to spool up. Unsure of what it should look like with the N75 dissed. I'd expect a k04 to spool earlier. Or could the map sensor be overreading? I will have to double check boost gauge to rule this out.

I havent tested wastegate pressure as yet but if it is stronger can i be pointed to some info on how to tune boost pid to enable N75 to control boost better.

Full log is too large to post it seems.

Hi,

I'm finding similar after adjusting LDRXN, LAMFA etc making my own little map. I think it may be because we havent adjusted the boost PID? changing this may mean we get less overshoot - i however do not know how to adjust it just yet and or what maps need adjusting. I may be totally wrong though. seems to control nicely after the initial overshoot.

EDIT: grabbed this from the s4 wiki :)

KFLDRQ2 - LDR PID Q2 (differential term) - adjust this to compensate for overshoot when your boost ramp meets requested. Increase it if you see a lot of overshoot. If you have undershoot, try increasing KFLDIMX first. Only decrease Q2 as a last resort.

First I'll be checking operation of the wastegate as it seems to have some boost creep when on wastegate only.

DO NOT TOUCH Q2 unless you are very intimately familiar with PIDs.

KFLDIMX is what you are looking for..

Either way, do not touch this until you at least do a little research on PIDs and how they work.

Tune out boost creep with KFLDRL

For a constant output from the PID, KFLDRL should compensate such that the actual resulting boost is constant.

Sorry guys, my bad! It's something I need to look into as well, every log I have has small overshoot and I'd like to make sure I don't have any :P

Is it just a case of adjusting dc on the last line?

Seems a bit crude to do that?

That is not the function of KFLDRL in ME7.
The function of KFLDRL is to make sure that when the PID reacts by 10% it actually is 10% of the regulation range.
What you have suggested to do is completely wrong.

OP:
You need to linearize the boost pid, because your engine is nothing like your software anymore.
For that you need to set CWMDAPP to 16, and then control WGDC using LDRAPP.
Then make similar pulls with 10% increments in LDRAPP. 0 to as high as you can go without damaging anything (but ideally just a bit higher than the target boost you want to run).
After that the data has to be processed and KFLDIMX/KFLDRL generated from it. It is purely a mathematic process.
When that data is correct, some real world tuning will be needed at the lower RPM ranges in high gear with KFLDIMX. And only then the Q0/Q1/Q2 have to be adjusted as per PID mechanics.

It is not exactly a simple task.

Thanks for the explanation. I did wonder if DP and filters would affect this. Clearly it has.

I will look into this further. I did see a post where I said to start pid from scratch. Is that the way?

should not be set to 8?

Read that here http://nefariousmotorsports.com/forum/index.php?topic=517.msg4013#msg4013 (http://nefariousmotorsports.com/forum/index.php?topic=517.msg4013#msg4013)

Which means that when the PID reacts by 0%, it is 0% of the regulation range.

Meaning if the output of the PID does not change, the boost should not change either.

In my XDF I have TLDOBAN.  I have read that this is zero 'd to help with overboost.

In my map it has 10.00 across the board. Would this help with initial overshoot?

No.

I have actually been doing this. I had issues with this as no matter what duty I put I LDRAPP, the wastegate seemed to be similar to 0%.  Further investigation led to me realising that at 90%, wastegate duty was showing ~31% actual. The XDF I was using that I had found on here had no calculation for the map.  This was corrected and I could then see changes.

I have logs upto 70% but haven't yet been able to translate with spreadsheets I have

Although it seems from reading the 2.7T tune thread, I may only need to tweak DIMX as I have a stock wastegate and the larger DPs have an effect on the WG Duties required .  

99% of all baseline first pass PID tuning is in IMX.

Great.

I can have a play with that.

I have done linearisation of DRL and seem to have dialled in Dimx fairly well but I large overshoot and cant tell from the logs howto adjust Q2, Map attached. Any pointer on what ide cells i should be adjusting?

There is an area where boost doesn't overshoot at around 4k but i think its helped by some load limiting. Not sure this is the best way. Is that IRL?

There is also some intervention after 6k that im dialing out but the load (rl_w) is way over requested
on some charts, Is that correct?

Log cant be posted for some reason

Does anyone know the ideal boost profile for a BAM / AMK K04 for LDRXN? and max boost?

Your Q2 map is most definitely defined wrong.

Not sure about requested load, need to see your original logs with all the rl variables

Why can't you post the log? try zipping it if it is too big.

Log zipped here
Ill check my defined map on winols about Q2.

I started using an xdf found in here, assumed it would be correct

Is it possible your MAF is scaled wrong? Your actual load should not be that much higher than spec.

Also, can you log mrfa, mimax, mibas and ps_w?

thanks :)

Maf is stock. Although i dont have an airbox and have a cone filter.

Mrfa_w is in the log, i can do ps_w but i dont have the ram locations for the other two.  :(

Thanks for pointing out Q2. Address steps were out

looks more like a map

If you can get somebody to find them it would be helpful (they'd have to do some disassembly work though).

ps_w might help us figure out why your load is so high. The cone filter may be interfering some with the MAF signal, but the difference you're seeing is pretty significant.

Also, that Q2 still looks very suspicious; the highest numbers in the map should correspond to more or less just before peak boost...

The Q2 is now the same as the stock file. 225 TT i've compare with a few files i have

In that case, it will need a lot of work.

Shift the entire thing up 1000 or 1500 rpm, and try to smooth out the rest behind it so its symmetric. (3d view might be most helpful here).

I have done this, Not flashed it on yet.

In the mean time i have logged ps_w

Looking at ps_w, seems like the maf need scaling down. Is this done In MLHFM or is there another cause?

It is the standard housing, The wiki seems to cover larger housings, not the standard one.

Not clear why your setup is reading high; any chance you can just try a stock airbox/intake?

Not really, there's no room.  ???

(http://img.photobucket.com/albums/v458/tshirt2k/rocco%2020vt%20archive/rocco%2020v/A0B7B0FD-A665-4683-878B-E1F20876FF9A.jpg)

Was thinking about Kfkhm. I read in another thread that ps_w can be reduced using this. I did try it and it did reduce, but it seemed to mess up fuelling so I reverted it back.

Comparing two files I have, one has a had Kfkhm highly modified in comparison to stock. I just read also that it is used to compensate for fuel.

If you lower MAF signal (either through KFKHFM or MLHFM) you'll have to compensate for fuel with KRKTE, KFLF, or FKKVS

The easiest way is to scale the MAF signal by a % and compensate with KRKTE.

If you have a bosch maf, you'll have to shift the whole MLHFM down by 200, scale it, then shift it back up.

Thanks for the info.

So let me get this straight. All 512 rows need 200 subtracted from? Then scaling by a % and then 200 added back on to them.

Is the scaling done by trial and error or does logs give a clue.

Also. In my XDF is it right that the voltage scale is all over the place unlike in winols where it is correct?
I only have a test version of winols to view full map definitions.

for bosch, yes.


Hard to say without knowing what is going on. If your MAF is reading too high (or you have a boost leak), your should also be running rich (assuming your KRKTE is correct).


Definitely not good.

Boost leaks have been triple checked, was first thing I did after getting maf signal too high dtc
Fuel follows requested fine. And fuel trims are good. I'm going to check maf part number. See if it's correct as seems to be no real reason for it to be wrong as it should all be standard.


I can't get map definition to match data source.
(http://img.photobucket.com/albums/v458/tshirt2k/rocco%2020vt%20archive/rocco%2020v/354D72DB-75E0-4AB0-B594-DB15A0019A91.jpg)

Figured it out using external manual and editing rows.

I scaled down MLHFM by 10% would this be enough? Too much? The load doesnt quite match requested but i still need to tweak DIMX. Feels better but fuel doesn't quite follow early on. I have increased KRKTE slightly.

Does the load need to follow requested exactly? Any maps that need to be adjusted?

Dude, that looks GREAT!

Seriously, good job. Get your trims in line (if you haven't already) and you'll be set.

Well done.

Thanks  ;D

A bit more reading i think.

Maybe I'm beating a dead horse by elaborating, but I'm impressed you did this on your own, by just reading, and from only questions in this thread.

Keep this up, you'll go far!

Post up any other issues/comments.

In particular, if anything you read seemed misleading or wrong (especially in the s4wiki), please let me know. Your feedback is super important.

Now you mention it..  ;)
I must say, without your responses pointing me in the right direction I wouldn't have gotten this far. A lot of the info I have searched for is conflicting. Everyone seems to have their own way of doing things. So thanks for that.

The wiki assumes everyone starts with a standard(stock) car. In reality people add hardware from the start, especially with conversions and it throws most of the theory off track.
Also it seems to base everything on larger MAF housings. In my case everything was stock on the engine but due to having a larger DP, front mount intercooler and a cone filter/silicone TIP it seems it has affected my maf calibration. There's no real info on the effects it can have. It has been touched on with various posts but nothing conclusive. Most of the time I was trying to figure out what could be wrong. Also the fact that all of the above was also throwing my wastegate linearisation out. I had to do that before even starting on the MAF calibration.

Everything had to be done in a certain order but not necessarily to the letter.

Your simplification of the scaling makes it easier.
In the tuned file I have, everything MAF and fuelling related  was messed with apart from MLHFM. My XDF seemed to be partly defined but my issue regarding the voltage scale was resolved  by looking at your 2.7t XDF and copying the row numbers into mine.  I could then see the curve. Again no info anywhere apart from 0.0977 *(row numbers) which only relates to winols. 

It seems now that now I have rl_w and ps_w closer to to where it should be, is it right that I can tweak any areas in the high load areas with KFKHFM to get closer to actual boost? Then I can sort fuel in those areas with KFLF or FKKVS? Or is that not necessary?

There are more questions but I do like to research before asking.  It's not my first time tuning engines. Just my first experience with ME7.5, much different to standalone.

Understood. The reason the wiki is written from that perspective, is that it is assumes that if you have a 2.7t, you're probably looking for either a stage 1 tune (stock everything, just ECU flash) or a stage 3 tune (turbos, injector, MAF)

You point is a valid one, though, there needs to be much more explanation about which map modifications are for which goal. I'll try to go through the wiki at some point to try to fix that. If you have SPECIFIC suggestions about wording, they are more than welcome, especially if you just want to log in and change the wording yourself!


So basically, fixing fueling is in two steps (most people are lazy and do it in one, either all in KFKFHM, KFLF, or FKKVS), the end goal being to get fuel trims near zero (or, for a narrow band car, add one wideband sensor readings to match req lambda).

1) MAF calibration (MLHFM, KFKHFM)
2) Fueling system calibration (KFLF, FKKVS)

As I said, most people are lazy and do it all in one step in one (or more) of those three maps (not MLHFM), depending on which axis values you like working with the most. You can too, if you like.

Now, if you are wanting to be exact, you can to do them one at a time, independently

for 1), typically, you'll have a MLHFM from the MAF manufacturer to start with. KFKHFM should be calibrated by comparing ps_w with actual boost (during WOT), and req load with actual load (in areas where you expect actual load to match req - e.g. req boost and actual boost are the same). You really can be arbitrarily far off with either (within reason) at the end of the day, though, as long as the discrepancy looks consistent (no really big swings either way).

Then you can move on to 2).

Now, FKKVS is SUPPOSED to be only for tuning returnless fuel system nonlinearities, but KFLF might not provide the granularity you need at high load (you tpically end up only getting  4 or 5 cells to work with for WOT fueling), so a lot of people do more tweaking in both FKKVS and KFKHFM to get fuel trims sane.

If you choose the KFKHFM route, you may notice that ps_w and actual load might start to wander from actual boost and req boost (respectively), but IMO that isn't a big deal, you really want your fueling to be right over having an accurate ps_w or load.

Long story short: don't worry about small ps_w or rl_w discrepancies, fueling is more important.

Hope that helps.

BTW none of that is in the wiki because of the "more than one way to skin a cat" thing... YMMV, I'm sure many will disagree with what ive posted.

Thanks for the explanation. Helps a lot. I'll do some more tweaking to see how I go.

Question on KFKHFM.

Are cell numbers based on lambda or a factor of some sort?

unitless scaling factor unrelated to lambda.

IMO this is some key info.  ;)

I'd like to do it this way using Kfkhm to get ps_w closer to actual seeing as I am in the ballpark with MLHFM. There is still  a slight discrepancy.

Once happy I will then go into fuel. I think I will use FKKVS and maybe use the FKKVs finder as it seems similar to the auto tune you get in tuner studio MS. Doing it manually would probably take forever.

IMO not really big enough to worry about..

My reasoning: odds are that the intake is non-linenar, not your fuel system, so in most cases, you can often let the trims tell you what is wrong with your MAF calibration, and not with your fuel (at least part throttle), so that is an alternate method:

1) get KFKHFM close with ps_w (not exact)
2) use trims to fix up KFKHFM for part throttle (assuming your TVUB is correct and KRKTE is close)

If you are finding you are shifting LARGE portions of KFKHFM around, you should probably scale KRKTE or mass scale MLHFM until the entire fuel curve ends up closer.

Not sure what you mean by "trims". I know you mean short and long term but how i can see them in some useful form in the logs.

Do you mean fr_w or % shown in vcds?

Edit: I've found variables to log

I seem to be going in the right direction with KFKHFM, fuel seems to be getting closer to target after many changes but  I'm having an issue with throttle cut after 6k. I'm not able to get a clean run to the redline.

I have checked out IOP and IRL and it seems high enough as does HBN. Is there anything else i'm missing

rlsol comes almost directly out of IRL... not sure why it is cutting.

Would it cut if the IRL comes out  much higher than requested?

Maybe iop is requesting too much in that area.

Something is causing slow path intervention, and it doesn't look like it is IRL/IOP..

have to dig through the rl_sol path a bit more, maybe I'm missing something obvious.

Do you have ESP turned off during your pull?

Could be something obvious like ASR.

Car doesnt have ESP. Unless there something active in the map

Going to have to log rlmax->IOP->mimax, and see if it is limiting mifa into KFMIRL. mrfa is properly pegged at 100, so mifa becomes the input into KFMIRL) Hope that makes sense.

Rearead this section:

http://s4wiki.com/wiki/Tuning#Requested_load_limiting

You may need more IRL for lower mifas...

Still, it is spikey, so something else is interfering with rlsol, not sure what yet.

Ah.. I thought mifa was the output of IOP  :-\

Seems that's where the issue halts Mimax isn't a variable I have in my file.

I'd try to disassemble if I knew how. ???

see if you can log milsol and milsolv

also miasrl and B_asr to make sure it isn't traction control.

There are a bunch other slow path limiters in MDBGRG (that generate the mibgrl limit)  but hopefully you won't have to trace those.

Also double check KFMLDMX and MLMAX. Looks like it is consistently triggering around 650kg/hr

MLMAX is set at 680kg/hr
KFMLDMX seems high enough against rpm.

I haven't got those variables either.

Does traction control still work even though there's nothing wired in, or wheel speed sensors??

Can it be disabled in the file to be sure?

Edit: I have removed abs module in cw_can_r it is 00'd

Look at your logs. Not high enough..

I have raised it to 800.

Will log again.

Logged again, Still cutting throttle. MLMAX seemed to make no difference
Added Misopl1 to the log as I've read that its the input to IRL. and it is changing at the point of the cut

mldmx_w is next.

If that is fine, then one by one, have to log mibgrl and look at every item in MDBGRG

If not mibgrl, then only miasrl and miges are left, but neither of those should be possible above NASNOTKL rpm (usually something low, like 960RPM)

See the FR for details.

Progress. It might be mitibgr_w, which cuts req load if you hit injector max duty for too long.

You're out of fuelling.

Cut boost up top, or get bigger injectors :)

I should have checked IDC first! my fault.

Hmm.

I did notice my Injector duty was high. I assumed the calculation was wrong due to RL issues.

I'll give it a try. Thanks

I think i may have to get a 4bar Reg as I think im around stage 2 anyway

If you are over 70% or 80% IDC, you need more fuel. IMO a 4 bar is not enough.. you'll ideally need bigger injectors or bite the bullet and cut boost.

Or both 4 bar and less boost.

4 bar is a good start though.

I bought a 4bar but decided to go for injectors instead.

Going for 60lb Bosch '298 EV14's. Will have fun trying to get them working.

So it Looks like the Injectors have cured the Intervention.  ;D

Before i swapped injectors I tweeked KFK to get trims into line. I needed to put the most number to 1' in KFK to get them correct.

Car fired up fine, Idle is smooth but STFT is -10% driving around at partial throttle trims are adding fuel betwwen ~2-6%, but WOT seems to need lots more fuel.  ???

Whats the best table to adjust? My FKKVS is not all 1's like in the 2.7t. I'm thinking krkte to increase overall fuel. Just idle will be richer.!

KRKTE is 0.05472

TVUB found on here.

2.7577   1.9282   1.3388   0.9975   0.7894

Assistance would be appreciated

Fuel

Seems my krkte and tvub are good.

Idle LTFT is -0.8% and partial is 0%

I'll correct the rest with KFKHFM and FKKVS

Where did you find that TVUB?

http://nefariousmotorsports.com/forum/index.php?topic=6670.msg67239#msg67239 (http://nefariousmotorsports.com/forum/index.php?topic=6670.msg67239#msg67239)