Print Page - MED17 Boost Control (onset)

Title: MED17 Boost Control (onset)
Post by: de_Fre on March 20, 2015, 05:45:57 AM

Hi guys,

I'm looking over boostcontrol on MED17.5 (2.0TSI). as I have a classic problem I guess.

When asking for boost say 1.3bar relative , I do get that boost BUT, at boost onset, I get N75 correction (from 96% down to around 75%) at 0.8bar relative (this is the stock boost level, so it looks like it activates the Proportional part of the PID control, I guess) then it corrects back to 96% and lets me go to 1.3 bar, the boost control is fine once it is close to target. This feels like a hesitation of the car.

Is there anyone who could help identify why this happens, why the N75 doesn't wait till closer to 1.3 to "activate" the PID or is my problem something else ?

I know people use tricks like building boost gradually in order to overcome this or tune the N75 limiter map to around 75-80% in the lower rpm's so you wouldn't feel this, or just kill the P-term in the lower rpm region to reduce the effect, but i'm looking to understand why this happens, which map(s) is (are) responsible.

Thanks for any help.

Title: Re: MED17 Boost Control (onset)
Post by: Tezotto01 on December 12, 2017, 09:29:19 AM

Any solution to this question?
I'm facing the same problem.

Title: Re: MED17 Boost Control (onset)
Post by: jcsbanks on December 12, 2017, 11:00:49 AM

May not be your reason, but that happens with the D part of PID feedback on many boost control systems.

Title: Re: MED17 Boost Control (onset)
Post by: vwaudiguy on December 12, 2017, 11:03:55 AM

Not going to be able to help much without decent logs, and/or posting your file...

Also, waiting for Nyet to chime in telling you to read up on PID's :)

Title: Re: MED17 Boost Control (onset)
Post by: Tezotto01 on December 13, 2017, 02:21:08 AM

I'll post the log.
Basically when you are doing an overdrive and if you ask for a little more load (without wot) the throttle opens 100% and the N75 cycle oscillates between 65% and 100% with this I feel the car oscillating the torque ....

Title: Re: MED17 Boost Control (onset)
Post by: focalpoint519 on December 13, 2017, 09:02:45 AM

any changes in KFVPDKLD or LDRXNLB, KFLDHBN?

Title: Re: MED17 Boost Control (onset)
Post by: NBR on December 15, 2017, 01:05:10 AM

I'm quite interested to know what maps pertain to the boost control on MED17 as it's different to the ME7/MED9.

What maps are you guys using to change the PID, N75 and WG Linearisation? Is it all contained in the LDRREG module or is there another module I should look at?

Title: Re: MED17 Boost Control (onset)
Post by: panos1975 on December 16, 2017, 10:40:23 AM

chck sections ATVLDSTE AWGTV......inside them you will find what are you looking for....

Title: Re: MED17 Boost Control (onset)
Post by: NBR on December 18, 2017, 01:34:45 AM

Thank you! I will have a look and do some reading/testing

Title: Re: MED17 Boost Control (onset)
Post by: NBR on December 20, 2017, 04:16:26 PM

Okay, so I've been doing a bit of reading and trying to understand using the FR and google translate...

I'm very far from understanding but i have a few questions and I'd like to know if I'm on the right track.
From what I've gathered KFTVLDST is the feedforward/base duty cycle map. The question I have here is it says that its used in application mode and that the variable B_tvkfldst is the input to the if statement to determine if it's used. Now I can't find any other reference to B_tvkfldst, is it set by a codeword or is it hardcoded so that the ECU always uses KFTVLDST?

The next is i see that KFWGV is used, with the P and I part added to it and then limited by KLWGMX. However the map seems a bit confusing, especially the row of zeros at 5800rpm (see attached pic). Is this because its expected that the PID controller would be in full control of the duty cycle at higher RPM?

I've also noticed that a lot of the time, the input and output variables to a module like AWGTV are not referenced in any other module, so thats where I'm getting stuck, because I don't know where the variable comes from and where the output variable ends up going or what the ECU does with the output of a module. Is this normal or am I missing something?

I still have to read through the entire LDRREG module to get some more understanding, but I would appreciate any help and hints you guys are willing to offer. Thanks once again

Title: Re: MED17 Boost Control (onset)
Post by: prj on December 21, 2017, 08:49:07 AM

Application mode is set via codeword, disassembly will show you which one and which bit.
Then the entire flow based precontrol can be removed, and replaced with a standard precontrol map, which can be populated from 0-90% wgdc runs.

IIRC though just setting it through the codeword had some consequences, so I patched something in the code. Can't remember what.

Title: Re: MED17 Boost Control (onset)
Post by: NBR on December 21, 2017, 09:10:41 AM

Thanks prj. I haven't tackled disassembly yet but I will give it a go using the guides here

Title: Re: MED17 Boost Control (onset)
Post by: woj on December 21, 2017, 09:14:40 AM

(Writing from memory, travelling without my laptop). On ME7.9.10 which supposedly has a very similar boost control, the cw is CWMDAPP, will confirm later. The downside of KFTVLDST is that it is full open loop, at least on ME7.9.10.

While at it, any of you could share the parts of FR that treat boost control? Either for the discussed MED17 or ME7.9.10 or equivalent.

Title: Re: MED17 Boost Control (onset)
Post by: NBR on December 21, 2017, 09:32:52 AM

Yip the MED17.5 does have CWMDAPP - codeword application without torque function.

Let me see if i can get IDA and try this disassembly thing

Title: Re: MED17 Boost Control (onset)
Post by: woj on December 22, 2017, 12:20:52 PM

I briefly looked at the description for MED17, unfortunately only the last stage of the control seems similar to ME7.9.10, all previous calculations are different. In particular, in MED17 I do not see HLDSTNGMT and related maps. This probably means that my statement about open/closed loop for KFTVLDST for MED17 does not hold.

Title: Re: MED17 Boost Control (onset)
Post by: prj on December 23, 2017, 11:53:21 AM

Quote from: woj on December 21, 2017, 09:14:40 AM

Completely wrong. CWMDAPP is not the codeword and it is possible to set only the pre-control to that map while keeping full closed loop PID.

Title: Re: MED17 Boost Control (onset)
Post by: woj on December 23, 2017, 12:11:48 PM

Quote from: prj on December 23, 2017, 11:53:21 AM

Completely wrong. CWMDAPP is not the codeword and it is possible to set only the pre-control to that map while keeping full closed loop PID.

Reading of CWMDAPP and setting a RAM bit:

Code:

        rom_7CE0:[F3,F2,B9,00]  movb    rl1, CWMDAPP_0B00B9
        rom_7CE4:[8A,F1,02,30]  jb      r1.3, loc_7CEC
loc_7CE8:
        rom_7CE8:[6F,88]        bset    PSW.USR0
        rom_7CEA:[0D,01]        jmpr    cc_UC, loc_7CEE
loc_7CEC:
        rom_7CEC:[6E,88]        bclr    PSW.USR0
loc_7CEE:
        rom_7CEE:[3A,88,02,6C]  bmovn   iram_word_FD04.12, PSW.USR0
        rom_7CF2:[D7,40,2C,00]  extp    #0x2C, #1

Choosing ot use KFTVLDST based on the value of FD04.12:

Code:

loc_085B1A:
        flash_085B1A:[9A,02,0C,C0]      jnb     iram_word_FD04.12, loc_085B36
loc_085B1E:
        flash_085B1E:[E6,FC,60,64]      mov     r12, #KFTVLDST_0AE460
        flash_085B22:[C2,FD,66,F7]      movbz   r13, nmot_b_engine_speed_F766
        flash_085B26:[C2,FE,BF,84]      movbz   r14, xram2_byte_0F04BF
        flash_085B2A:[DA,00,04,67]      calls   read_byte_map_2d_scales_6704
        flash_085B2E:[C0,8C]            movbz   r12, rl4
        flash_085B30:[5C,8C]            shl     r12, #8
        flash_085B32:[F0,DC]            mov     r13, r12
        flash_085B34:[0D,10]            jmpr    cc_UC, loc_085B56
loc_085B36:
        flash_085B36:[9A,29,03,20]      jnb     iram_word_FD52.2, loc_085B40
loc_085B3A:
        flash_085B3A:[F2,FC,6C,9B]      mov     r12, fallback_TVLDST_0F1B6C
        flash_085B3E:[0D,0B]            jmpr    cc_UC, loc_085B56
loc_085B40:
        flash_085B40:[8A,01,04,50]      jb      iram_word_FD02.5, loc_085B4C
loc_085B44:
        flash_085B44:[F3,F2,DD,87]      movb    rl1, xram2_byte_0F07DD
        flash_085B48:[9A,F1,03,60]      jnb     r1.6, loc_085B52
loc_085B4C:
        flash_085B4C:[F2,FC,DA,A3]      mov     r12, mapres_TVLDSTDPW_0F23DA
        flash_085B50:[0D,02]            jmpr    cc_UC, loc_085B56
loc_085B52:
        flash_085B52:[F2,FC,94,64]      mov     r12, TVLDSTAUF_0AE494
loc_085B56:
        flash_085B56:[F6,FC,80,A3]      mov     tvldstr_w_0F2380, r12
        flash_085B5A:[F2,FC,96,64]      mov     r12, TVLDSTEMN_0AE496
        flash_085B5E:[F2,FD,80,A3]      mov     r13, tvldstr_w_0F2380
        flash_085B62:[F2,FE,98,64]      mov     r14, TVLDSTEMX_0AE498
        flash_085B66:[DA,02,78,85]      calls   trim_unsigned_028578
        flash_085B6A:[F6,F4,82,A3]      mov     tvldste_w_wastegate_DC_0F2382, r4

There is no PID control over the value read from KFTVLDST whatsoever, there is one over one of the pre values (wastegate strong, turbine mass flow, and what not) that lead to what I marked as mapres_TVLDSTDPW_0F23DA.

And yes, that is for ME7.9.10, not MED17, in another post I explained that looking at MED doc tells me it's a whole different story, which I am sure you can explain in detail to everyone ;)

Apologies if my variable names are not up to your standards, I know some of them are wrong.

Title: Re: MED17 Boost Control (onset)
Post by: prj on December 23, 2017, 12:20:48 PM

MED17.5 works completely different, and this is what we are discussing here, not your fiat ECU.
I don't see why you keep bringing up an ECU that is two generations older when we are talking about Tricore MED17. MED17 is nothing like it, and MED17.1.1/MED17.5 are also completely different between each other.

Title: Re: MED17 Boost Control (onset)
Post by: woj on December 23, 2017, 12:45:01 PM

Well, you said in another thread when I asked about ME7.9.10 boost control "sounds like MED17", clearly not, I wrote what I wrote still believing that's the case, and rectified my statement shortly after I found out that it is not. My mistake is stupidly believing Bosch would have and consistency in their developments.

Title: Re: MED17 Boost Control (onset)
Post by: prj on December 24, 2017, 03:05:52 AM

ME7.9 has boost control somewhat similar to MED17.1.1, albeit with some differences. MED17.5 discussed here is a COMPLETELY different animal.

Title: Re: MED17 Boost Control (onset)
Post by: gman86 on December 25, 2017, 06:07:21 AM

Quote from: woj on December 23, 2017, 12:45:01 PM

You must be new here. Don't expect a straight answer regarding a platform even remotely profitable.

You'll get enough fluff to say "I know more than you" and the rest is just shit. It's just a cock waving exercise by some well informed virgins.

(https://i.ytimg.com/vi/7tTfL-DtpXk/maxresdefault.jpg)

Title: Re: MED17 Boost Control (onset)
Post by: woj on December 26, 2017, 07:31:23 AM

Quote from: gman86 on December 25, 2017, 06:07:21 AM

You must be new here.

Registered ages ago, active long enough to see what is going on. No worries, I don't mind, my culture of origin taught me to bear much more than that ;)

Title: Re: MED17 Boost Control (onset)
Post by: tezotto on January 04, 2018, 05:09:41 AM

I did some testing and left KFPWG OEM making minor adjustments to KFIWG.
At first it seemed satisfactory, I will walk for longer to evaluate and put the result.

Title: Re: MED17 Boost Control (onset)
Post by: Dave9n3 on January 04, 2018, 05:31:12 AM

Anyone got the MED17.5 FR and willing to share?

I'm not sure how people get hold of the FR legitimately anyhow - assuming its still new enough tech for people to want to charge for it which is fair enough!

Title: Re: MED17 Boost Control (onset)
Post by: tezotto on January 04, 2018, 05:43:16 AM

Aqui está:

http://nefariousmotorsports.com/forum/index.php?topic=13597.0title=

Title: Re: MED17 Boost Control (onset)
Post by: prj on January 05, 2018, 08:39:44 PM

Quote from: gman86 on December 25, 2017, 06:07:21 AM

I think you need to go back to the hole you crawled out of and come out when you actually know something.

I did not have FR when I tuned this ECU. I reverse engineered the PID control and the configuration from the tricore assembly using IDA Pro.
Sorry if I don't remember every single parameter and variable name off the top of my head, because I don't tune this old shit most of the time.

For those actually doing some tuning - if you know how MEDC17 addressing works, look at the access to IIRC the first parameter in the module.
If the turbo is changed then just changing the PID will not help you when the precontrol is massively wrong.

Title: Re: MED17 Boost Control (onset)
Post by: gman86 on January 05, 2018, 08:45:20 PM

Quote from: prj on January 05, 2018, 08:39:44 PM

I think you need to go back to the hole you crawled out of and come out when you actually know something.

Case in point. If the shoe fits, and all that.

Considering I don't do tuning for a job, I feel I know enough and am happy with my rate of learning as a hobby tuner. You're the equivalent of a chief engineer at Boeing coming onto a model aeroplane forum and waving his willy about. It's been stated that you have a "unique type of arrogance". I think that stems from the fact that your mum has given up trying to get you out the spare room.

Title: Re: MED17 Boost Control (onset)
Post by: prj on January 05, 2018, 08:47:05 PM

Quote from: gman86 on January 05, 2018, 08:45:20 PM

Keep talking. You have absolutely nothing to contribute, but you really can't keep your mouth shut. Class.

Title: Re: MED17 Boost Control (onset)
Post by: gman86 on January 24, 2018, 09:29:51 PM

Quote from: prj on January 05, 2018, 08:47:05 PM

Keep talking. You have absolutely nothing to contribute, but you really can't keep your mouth shut. Class.

Absolutely nothing? That's wildly inaccurate. I contribute what I can, where and when I can.

I love the "can't keep your mouth shut" comment. What relevance does that have? What authority do you have to tell anyone to keep their mouth shut? You're a cock, and a monumental, smug and arrogant little one at that. One that I dare say wouldn't have the minerals to talk to someone to their face as you do on this forum.

Title: Re: MED17 Boost Control (onset)
Post by: prj on January 25, 2018, 02:58:22 AM

Quote from: gman86 on January 24, 2018, 09:29:51 PM

Keep talking, we're listening. Anything else useful you have to say?
You have contributed absolutely nothing to this thread apart from being an obnoxious twat.

Title: Re: MED17 Boost Control (onset)
Post by: 316LV on January 26, 2018, 04:20:55 PM

Rodney King once asked "Can we all get along?". Well sorry Rodney, apparently not on Nefmoto ;D

I kid but I don't want to see Nye hit anyone with the ban hammer. Maybe time to agree to disagree and move on. Just a suggestion. Feel free to tell me to go fornicate with myself though.

Title: Re: MED17 Boost Control (onset)
Post by: carlhook on December 04, 2022, 03:38:52 PM

Quote from: de_Fre on March 20, 2015, 05:45:57 AM

Did you ever figure this one out, Im having a similar problem with my car, I think.
Can you share your map pack or ori/mod to compare?

I have cczb with med17.5 and a patched DCWG file, but I think my WG I-part maps are wrongly defined.

Title: Re: MED17 Boost Control (onset)
Post by: quattro85 on December 05, 2022, 02:00:25 AM

I'm not 100% sure about this, but I think on boost onset duty cycle of N75 is brought to 96% not by boost pre-control algorithm, but with D part of the PID.
It depends on boost gradient and prediction time to calculate when boost will go above desired. As soon as this event occur it will pull out this D part.

I don't think it have something in common with stock boost level - just coincidence.

Title: Re: MED17 Boost Control (onset)
Post by: prj on December 05, 2022, 03:47:09 AM

Question is answered instantly by using proper logging and looking at FR.
Then you can see directly what affects what.

For example on S18 there are three different boost controllers with different strategies.
Without logging impossible to tell when what is active.

Not the case on this ECU (there are some MED17 with 2 different controllers), but still, if you don't have correct logging, it's very difficult to get anywhere, because you simply don't see what is going on.
So you can change a million maps a million times, or you can just log the correct parameters and get there in 2-3 changes.

Title: Re: MED17 Boost Control (onset)
Post by: carlhook on December 05, 2022, 05:16:11 AM

Quote from: prj on December 05, 2022, 03:47:09 AM

Darn, I was looking for a simpler fix/ solution I can pay for without jumping in the FR as I really do not want to. I have no aspirations to tune these ECU's, just messing with my own car.

What I get it a oscillation in boost on my Stage 1 file with stock PID and Patched KFTVLDST disabled.

So I bought your VehiCAL, and it looks like I need the Advanced Protocols + patch the ECU to be able to log?
Is there a cheat sheet of parameters to log for specific issues?

Title: Re: MED17 Boost Control (onset)
Post by: prj on December 05, 2022, 08:21:50 AM

Quote from: carlhook on December 05, 2022, 05:16:11 AM

So I bought your VehiCAL, and it looks like I need the Advanced Protocols + patch the ECU to be able to log?

Probably, but the right place for those questions is support e-mail, not this forum.

Quote

Is there a cheat sheet of parameters to log for specific issues?

No, you are going to have to learn.

Title: Re: MED17 Boost Control (onset)
Post by: fknbrkn on February 22, 2024, 04:49:02 AM

What about using CWAGTV = 4 and KFWGV as precontrol?
Only thing here confuses me - using rlsol as the axis, what if i patch it to plsol ?

Title: Re: MED17 Boost Control (onset)
Post by: prj on February 22, 2024, 06:46:15 AM

Quote from: fknbrkn on February 22, 2024, 04:49:02 AM

What about using CWAGTV = 4 and KFWGV as precontrol?
Only thing here confuses me - using rlsol as the axis, what if i patch it to plsol ?

You can do that.

NefMoto

Technical => Tuning => Topic started by: de_Fre on March 20, 2015, 05:45:57 AM