NefMoto

Hi, I started messing with my tune again to get rid of an annoying problem that persisted ever since I got my car with it's original stage 1 tune.

In a few words, I think I have some kind of interventions around 3000rpm at WOT, expressed in slight to hard vibrations in the cabin and so far I have no idea what causes that...

nothing of the following helped:
- different KFMIOP/KFMIRL settings
- lowered KFKHFM
- increased KFURL
- KFMIZUFIL/OF maps maxed

If I limit load near 155 (about 2000mbar) I have no problems. KFLDRL is linearized, DIMX and PID control are set correctly, IZUFIL/OF maps are stock now and I didn't try disabling torque monitoring.
The car is a '01 A4 B6 1.8TQ, AVJ, with custom intake, 2.75" turbo-back exhaust, hybrid K04, S3 injectors, return type fuel system with 4bar FPR, FSI coils, etc. I can attach the bin & definition if needed.

I don't have the mibas, mimax and misolv variables in my ECU file to log, so if someone has them I'd be very happy if he'd share them :)

I will appreciate any help.
Thanks in advance.

More graphs here, different IOP/IRL settings... Light vibrations @ 3200-3500RPM

Here are the graphs from the run that I had no problems. I lowered KFURL @ 3000RPM by 1% to see what happens (which I later saw as a mistake).

I still don't understand what is going on... I will appreciate any help. Thanks

...further KFURL and IRL/IOP tuning, no vibrations in following logs (graphs). Now, for the same boost level, ME7 requests more load. Is this right or it should be the other way around?
BTW the car feels slower in this RPM range now.

I still have the problem, especially when IATs get low. Here I post comparison graphs between two runs - the first one is OK and the second has moderate vibrations in the cabin. The vibrations are felt at 2900-3300rpm and are reflected in zwsol jumps towards zwopt. I also switched on intake cam advance (NWS) in WOT, like the S3 and TT setting, just to try the outcome, but I don't think it affects my issue.

Anyone like to share any suggestions?

I just made a few runs with torque monitoring switched off through CWMDAPP=1 - the engine had trouble maintaining idle, but it had no problems at WOT, except the vibrations problem - still persists. Could this be the turbo surging, or other hardware problem? I read somewhere that K04 turbos surge at reasonably high loads around 3000-4000rpm.

Here's the log.

I also logged with CWMDAPP=8, there was no change...

I would really appreciate it if someone could help.

Could be ARMD.

Hi, I did set the last rows of KFDMDARO, DAROS, KFDMDPO and KFDMDADP to 100 a long time ago, so I think that would have switched the function (incl. dashpot) off?

Edit: I just saw I didn't touch KFDMDAROS... and I'm not sure if I defined the map right. I'll have to read the ARMD topic again, if I remember right there was a switch to turn it off completely and I'll try that...

Thanks

OK, I FF'd all of KFDMDARO, DAROS, KFDMDPO and KFDMDADP (I'm not sure which is which in my bin, that's why I did this). I think I obviously lost the dashpot function as the car was bucking hard whenever I touched the gas pedal, so maybe I succeeded turning off anti-judder, but the bad part is I still have the annoying vibrations. Here's the log and graph showing that zwsol still sits below zwbas. Maybe I couldn't completely turn off ARMD; I can't find the temperature thresholds or CWARMD to try and I don't have the ARMD variables for my ECU in ME7Logger. Any thoughts?

Yes, you're going to have to use a disassembler to find RAM locations to log.

I was afraid I was going to have to do that, otherwise it's just guessing, but do you think there is any possibility my issue could be hardware related?

If it is strong shuddering it may also be misfires... other than that, hard to say.

Yes, shuddering is strong when IATs get low. I'll try with lower timings in the problem area and I'll log knock sensor voltages, but I think I did this before and there was no KR activity, although shuddering was still there. I'll probably end up with lower load at IAT<50degC through KFTARX and leave it this way. I flashed this ECU about 200 times and I don't know if it can withstand much more :) .

Many thanks for your comments.

Post your bin and I will find ARMD vars for you.
Lemme know which ones you need.

EDIT: D'oh, it was over a month ago. Still, poke me via PM if you still need assistance.

Yep, but I still watch this thread :) I'd be very happy if you could help me with my missing vars. I can't do anything more without logging.

Just give me your bin and name them vars!  ;)
EDIT: it doesn't have to be the actual bin. Stock version is just fine.

B_zwvs
B_llrein
mibas
mimax
misolv

I'll post new logs as soon as I have the new variables.

Many thanks

And here's the actual bin, if anyone want's to look. This version doesn't have the stuttering, except in a very specific and narrow IAT range about 32-35degC, but requested load is limited (a lot) through KFTARX under 3500rpm... :(

B_zwvs FD8C.3 (word, 0x8 mask)
B_llrein FD82.8 (word, 0x100 mask)
mibas_w 3826D8
mimax_w 384BE0
misolv_w 3826BE

If you need anything else, just ask away. It takes 3 mins to find them now. ;)

Here's some more logs including the new torque vars /huge thanks to nubcake for that ;D /. I upped the load a bit in order to generate some stuttering. No problems in 1st run (3rd gear) and all the rest has the stuttering (5th gear) around 2600 to 3100 rpm.

One bit I forgot to mention earlier - the stuttering doesn't exist before engine temp reaches 90C on the dash - there are no problems even at 85C no matter what the IATs are. I'll try to log that.

Surely feels like talking to yourself sometimes, huh?  :D
Try temporarily FF'ing TMAR at 1182B to see if it's indeed ARMD.

Also, in case you haven't figured this out, you add those bit vars to .ecu file like this:
B_zwvs            , {}                                , 0x00FD8C,  2,  0x0008, {}        , 0, 0,            1,      0, {}
B_llrein            , {}                                , 0x00FD82,  2,  0x0100, {}        , 0, 0,            1,      0, {}

Yep, sometimes feels exactly like that :D . Thanks for your interest and support.
Yesterday I had some time and flashed the car with FF'ed TMAR and I upped ARX below 50 deg C to request more load and log what happens. As expected, I had stuttering from about 2900rpm to 3400rpm. It feels like the source of the stuttering comes the back of the car, but I can't be 100% sure, as everything resonates in the cabin. B_zwvs was zero until about 4200 rpm (then I stopped accelerating) in that run and B_llrein was constantly 1. B_zwvs was also going to 1 in lower load situations.
I still have no idea what is going on and my "solution" is lowering desired load to 150 @ 3k rpm below 50 deg C. IATs of 50 deg C or more give no stuttering at loads of 175 or more.

Any suggestions are welcome :)

P.S. When I bought the car it had even worse stuttering from as low as 2000 rpm in lower IATs (it had a tune with the stock K03 setup). My setup now can't reach those load levels at low rpm so there is no stuttering there.

B_llrein is supposed to stay at 1 AFAIK, and we have effectively eliminated ARMD by FF'ing it.
Coming from the back of the car? Hm, maybe it's misfiring? Too low coil dwell in that rpm/load area? Try logging fzabgs_w.

Did you ever find the cause of this problem? I've been dealing with a similar or exactly the same issue. Feels like I've been chasing my tail trying to track down whats going on with this wot jerking

Unfortunately I didn't and I sold the car last year. I logged everything coil related, pushed dwell times up to stock values, but nothing helped. I just ended up lowering the load as IATs go down, which eliminated the issue nicely. I did not feel any power difference, compared to the higher load at higher IATs.

Ok so tonight i swapped out all my coils and checked my spark plug tq specs and the problem is gone! Dont want to get too excited but tonight was the first night in months i was able to do consistent back to back pulls with no hard shuttering at wot. I was about to give up because ive replaced and checked so many parts, along with two motor pulls to get to the bottom of this.
I really hope it doesnt xome back but if it does first thing ill do is replace my coil packs again. Now i remember why i love this car lol

Forgot to mention i also swapped out my fpr. I noticed the one i had in had a crack in the filter. Dont think that was the problem but who knows...?

Happy to hear you solved your issue :) My coil packs were new at the time, but maybe I used the wrong ones (can't find the exact part #, but they were OEM from a Golf 6 2.0 TSI). I also had the issue with the original coil packs on the tune that the car came with for the stock k03 turbo. Do you use the stock coils or you put something else?

On B6 I solve that problem with higher (6bar) fuel presure on rail. My guess is that fuel is not enought good atomized and at that low RPM engine can burn all, what lead for not completly burn fuel, what cause missfire.
Now I am again at 4 bar stock FPR and it again have hard vibrations at pull aproxx 3000 RPM

I do still use the stock coils. I just do t see the use for upgrading to the 2.0 coils. My car was running great before this problem started so I k now the oem coils ar more then enough to handle ko4's on e85.

So guess what? problem sorta came back. Now its been intermittent but I got a evap code for small leak which I believe I found on the hard line that travels from the bay to the charcoal canister in the rear. Looks like there's a small crack in the line right behind the driverside tire.

I just added a bunch of torque variables to my logging file. I'm going to go do some pulls and post up the logs here when I'm finished so possibly someone who takes a look at them might notice some fuckery going on in there

First gotta go fix that hard line

quick question. What Torque variables do I need to log?

For the torque variables you may check either earlier posts here (like #20) or my other topic, as I have really forgotten such specifics.

In regards to the hardware that I did not check on my car, before I sold it, was the injectors (bought second hand from an S3), the fuel regulator (again second hand 4.5bar for return line system)  and EVAP valve. Considering the latest replies here I do believe that the injectors needed a flow test on my setup and they may have caused my issues. This engine may be more sensitive to flow pattern and atomization/pressure than I had anticipated. However, I am not sure whether such issues would be depicted in the logs, at least no one suggested this earlier looking at my logs.

It is all laid out explicitly in the S4wiki tuning page.