i just read this all last nite, very impressive. i am very impressed that someone could firgure this out before the manufacturer. as was mentioned ,they dont seem to be too concerned so maybe thats why. my MCS is aMay 03 build #td69722. please add me to the list. my yo yo is generally quite mild it seems, compared to what ive read: however it is there. i have a stumble as well, esp. when cold. is this fixed with the v36 update? i live in bham,al. and the closest dealers are in atlanta so i was going to wait until my 10,000 service to have that installed. ill email the above letter to one of the atlanta minis contacts. again Ryan thanks for all the great work.

 

Welcome to NAM orthomini and jgalvin. Just to clarify - V36 was designed to fix the Stumble, which was found to be strictly a software problem. V36 is currently available at all dealerships. Hopefully, with all the channels of communication going to MINIUSA, the combination hardware/software fix for the Yo-Yo will be available relatively soon [crosses fingers]

Update: My 2nd full tank with Ryephix #1 yielded 23.6MPG, a significant jump up from 21.1 of the first tank. My commute is very steady, so I would guess the increase is from the adaptive logic learning to optimize the efficiency with the bypass valve tied shut. Still off from my 26MPH average with the stock setup, but the 10% loss is worth it when you factor in how perfect the engine feels with no bypass vavle mussing up the engine response! The Ryephix #2 does help maintain most of that bypass-valve-less feel (except on abrupt throttle transitions, where the bypass-valve-less setup is primo), though I haven't gone through a tankfull yet to calculate a mileage delta.

Cheers,
Ryan

_________________

 

Add me to the yo-yo list
TD57170 08/02

 

hey JustGo4It_: what does the Yo-Yo VIN Registry look like now?

my dealership is still waiting for the replacement ECU, in the meantime I'm going Karting Hey, if I don't get some quality drive time in, I'll go nuts!

P.S. We're famous Check out Bridger.us/MINI

 

Adding myself to the Yo-Yo list. 11/03 Build 04 MCS. TD78632. No stumble. Yo-Yo is most notable in second gear under moderate acceleration and more apparent going uphill. Keep up the good work. Hopefully MINI will respond with an approved fix. :smile:

 

Hey! MINI Division just popped in here
https://www.northamericanmotoring.co...forum=2&26
and gave us the 'ol run-around! :evil:

 

Ryan, v36 did help my yo-yo though. 2nd gear was worst, now it is not bad enough to fuss about. The amd is supposed to fix this as well have you tested yet? I pm'd you but I know you are busy.

Thanks , If there is a fix I'm sure you-you will find it

 

>>Hey! MINI Division just popped in here
>>https://www.northamericanmotoring.co...forum=2&26
>>and gave us the 'ol run-around! :evil:

Well, at least we know they are *periodically* checking this site. Now all we need is some follow-through from the BMW/MINI folks to pressure Siemens for action.

Ryephile has given it to Siemens on a silver platter. However, I'll bet you big bucks that, ultimately, it will be the Siemens folks (not MINI) who have the responsibility for this one. Remember, effecting the fix means correcting the ECU's servo controller overshoot programming bug which is written by Siemens.

My money says BMW/MINI will do nothing along the lines of a bypass valve modification because of the cost involved in parts and, especially, labor. And when you think of things from MINI's "business model" perspective, it makes good business sense to hold the vendor responsible for the quality of the product (software) which they supply. It's like us holding MINI (*our* vendor) responsible for the quality of our MINIs.

Thus, if there is something going on behind the scenes, it is probably MINI raising a product quality issue with Siemens. I would guess that Siemens is way bigger as a corporation than BMW, so these discussions probably need some constant urging on BMW's part.

I say this to propose that the fix isn't as simple as BMW/MINI getting off their korporate keesters and applying some engineering know-how. Instead, I believe it is more of a vendor and quality management issue on MINI/BMW's part. Undoubtedly, BMW/MINI will be politically compelled to present a rock-solid case to Siemens that a product quality issue exists before Siemens will be expected by BMW/MINI to dedicate themselves to a fix. In this regard,
Ryephile has presented BMW/MINI with diagnostic methods and realistic data samples for them to make an initial case to be heard be Siemens.

As far as timing, Siemens was in the US working on the stumble fix this summer yet it took until Nov/Dec for V36 to hit the dealers. So...even if Siemens were addressing the yo-yo in the US right now, we probably wouldn't see the corrected ECU code (V36.1???) until, say, late spring or early summer.

Now...about an aftermarket opportunity for that stiffer diaphragm spring...

My 2 pence,

 

Ryan,
We are at 53 so far, I'm sure there are tons more out there from looking at this list.

TD50353 03/02 travelkids
TD51104 05/02 911RSAmerica
TD51401 05/02 2Cool
TD53564 06/02 cpeters
TD57170 08/02 weeber
TD58121 10/02 ScottG
TD58445 09/02 RECOOP
TD60679 10/02 DaveNagy
TD61199 11/02 cooper44
TD62476 11/02 mudshark
TD64498 12/02 Minimoto
TD67984 ??/03 jgalvin
TD68072 04/03 SB
TD68136 04/03 coopstas
TD68953 04/03 Darxar
TD69237 05/03 mmanasas
TD69433 05/03 allen_shelton
TD69664 05/03 Tugboat
TD69722 05/03 orthomini
TD70585 06/03 Wastik
TD70666 06/03 agokart
TD71389 06/03 manoo
TD72531 07/03 brit-in-usa
TD73370 ??/03 reshultz
TD73852 09/03 minionrails
TD74156 ??/03 fishey72
TD74337 09/03 KatanaPilot
TD74370 09/03 Ken G
TD74679 09/03 Greg B
TD74723 09/03 apexer
TD75054 09/03 mczinn
TD75106 09/03 fuzzyface
TD75257 09/03 dimi_mcs
TD75554 09/03 MidMichMini
TD75586 09/03 Koopah
TD76176 10/03 Ryephile
TD76442 10/03 Chad B
TD76754 10/03 JustGo4It_
TD77119 10/03 countrym
TD77442 10/03 LeeL
TD78393 11/03 johnnycircuit
TD78632 11/03 mgessouroun
TD78920 11/03 h_lank
TD79087 11/03 earlyapex
TD79661 11/03 Parklife
TD79674 11/03 stew7710
TD80285 ??/03 ZFXR
TD80331 12/03 hnbrown
TD81147 12/03 jdgross

no vin 06/02 capsfan13
TD ???? 09/03 Spanky_03
no vin 09/03 mbur1024
no vin 12/03 zfxr

 

Please, add me to the list.
TD75287

Awesome info!

 

er, forgot my build date

TD75287 10/03 build

 

Yah...I second the opinion that Ryan's a little mechanical Genious If he were a businessman too he'd be on Mini USA's payroll...they owe him a salary for doing their homework

 

--->Sid; I know all too well that MINI "owes me one". They also owe my co-workers, and agokart too.

--->Koopah; great business insight! What makes matters even more pathetic for Siemens, is this PID damping adjustment is VERY easy to implement; like a 30-minute job total for the engineering team. My co-workers have offered to even do data-collection; Siemens couldn't get an easier fix if they asked for one! Unfortunately, Siemens has already demonstrated their utter incompetence; how many versions of software in two model years? I know there were some scattered and awkward times near initial release, but they've had TWO YEARS to get their junk in order. As agokart realized last week; "We've solved an issue in two weeks what MINI and Siemens haven't been able to even figure out for two years!" I'm sorry if I'm being condescending right now to them, but there is no excuse for incompetence. I think it's nice that MINIDivision is at least trying, but for goodness sake, I've already made numerous complaints to ASKMINI about the Yo-Yo, with ZERO results from MINI. ASKMINI is not setup to deal with actual new problems, only to redirect customers to their local dealership. While my dealership has been quite helpful, they honestly lack the capability to diagnose let alone solve this two-part issue. This is case where actual work has to take place, and MINI needs to step up to the plate and claim responsibility for their screw-up. I am getting tired of pouring my heart into this and getting a solid cold shoulder from MINI.

As for aftermarket bypass valves; it certainly is a step in the right direction; though I very much dislike having people pay out-of-pocket to fix someone else’s (MINI/Siemens) mistake. I'm sure if I spent more time on the unit itself, I could obtain even more refinement from a drivability and economy perspective. I could also have new-spec springs manufactured, to maintain consistency among bypass valves. The problem indeed, is that it would increase the price of the valve, plus (as you mentioned) the installation is a pain in the butt. A simple zip-tie and 10 minutes of DIY versus hundreds of dollars in parts and labor may not be worth it for many. However those that are interested in the performance and tractability improvements from a redesigned bypass valve, could justify the cost.

Thanks for listening,
Ryan

 

Yeah, what he said.

 

slight update - I bring MM2 back into the dealership Monday morning to have the ECU (or in BMW speak: the DME) replaced, to rule out any physical problems with the ECU itself. I honestly don't expect any change in output, however this slightly shotgun approach is basically the only possibility I see remaining. You'll find out when I do...

...until then, Motor-On,
Ryan

 

I always thought that while Siemens manufactures the ECU,
it is some US company in North America that wrote the code that runs on it.
All the re-writing and testing done to take care of the stumble was done by that same company (can't remember the name, starts with a P??).
?

 

Quick question/comment/idiot observation (all laugh at the new guy...)...

If '04 are most suceptible to yo-yo, could the earlier models have a stiffer spring or a different design on the by-pass valve? If so, then we should be able to get springs that fit easily (maybe).

On another note, I'm execting my baby late March, it's waiting for a boatr to fill up and then sail for Denver via LA. All the talk about the yo-yo has frankly got me a bit worried. How bad is it really? I mean, I have been driving American cars for quite some time and have gotten used to 'quirks' in the systems. Is the yo-yo a 'quirk' or a bone-jarring, take it to the nearest Priest for an exorcism? What is the RPM range which this occurs (1000's of RPMs?) Does it happen all the time or just when you first getting going from cold? I'll appologize in advance if the answers are somewhere else and I'm too lazy to look it up, but I want to know what I'm up against.

Thanks for the time and I hope to talk about the fun runs in the future!

 

--->bobhighley1: First off, Welcome to NAM :smile: We're here to help, so I'll try to address your concerns as accurately as possible. The Yo-Yo can be viewed as a quirk. At best your MCS will be one of the non-affected ones; at worst your co-pilot will think you can't control your throttle pedal to save your life. I generally classify the Yo-Yo as a moderate annoyance; it's always there unless you drive very slow or wide open; neither exemplifies my driving style on the road. The Yo-Yo is more prevalent in 2nd and 3rd gears during medium acceleration; this is due to the typical relationship between throttle angle and engine load (torque). The Yo-Yo seems to be more noticeable when the engine is cold, and exorcism will not save cure your Cooper S from the Yo-Yo

Having been driving around with A) a tied shut bypass valve, and then B) a stiffer bypass valve return spring, I can tell you that I do not miss the Yo-Yo at all! I still get frustrated with the horrible throttle body overshoot, which makes accurate throttle pedal input to throttle body output all but impossible near the transition between closed loop and open loop operation (near 80% throttle position). The effect is it makes the car unpredictable in what the throttle is going to do versus your inputs. Recently, it's made brisk exits from parking lots on slippery surfaces rather dangerous, as I can't predict very accurately how the throttle will react. The result is either too little acceleration or a sudden burst of WOT.

--->MG-BGT: I was under the impression that Siemens owned the ECU design and code, and subsequently had to do any and all alterations to the module both hardware and software. Hopefully this structure will be better understood in the following days/weeks.

Motor-On,
Ryan

 

Ryan, the E-gas pedal in the MINI works more like an ON/OFF switch than an actual power regulator. In a couple of occassions, I have experienced sudden outbursts of power but I have learn to modulate it.

Otherwise, no yo-yo issues here to speak of!

 

Thanks Ryan,

I don't think this will dampen my MINI Motoring mojo! I will keep watching for a permanant fix to the problem, but will make sure I don't drive too 'moderately' !

Later,

Bob

 

still zip tied and loving it.... it will take a total of 5 minutes to unzip and rezip if/when it goes the 150 mile round trip to dealer...

for the records s/n TD67615... build approx 03/03

let's see if MINI is watching closely enough to track my s/n and persecute me for unauthorized mod's >>if<< the blower dies.... :evil:

 

>>still zip tied and loving it.... >>

tme,

How's the mileage with the zip tie? Did it take a big hit?

 

>>--->MG-BGT: I was under the impression that Siemens owned the ECU design and code, and subsequently had to do any and all alterations to the module both hardware and software. Hopefully this structure will be better understood in the following days/weeks.
>>
>>Motor-On,
>>Ryan


Ryan is correct; Siemens is responsible for the ECU code. This was confirmed to me by MINIUSA in a discussion about the (now fixed) Stumble. Siemens may have used a third party to execute blackbox testing of their V36 code in the southwest this summer...perhaps therein lies the "P" connection.

 

I just called 1.866.ask.mini and asked to speak to a customer rep about yoyo. Every one should do this, too.

She explained that I must direct my concerns directly to the dealer. Of course this is correct, but it is also a bit circular logic because my dealer's sales person and sales manager more or less had blank stares when I mentioned yoyo. And the mechanics installed v36 at my request as it was the only "fix" available (it is not, and it didn't).

We need to register our comments at every level to be sure we are heard. She mentioned that they do monitor the websites, and she looked up the YOYO CHRONICLES as we were on the phone, and she promised to pass on my comments, and I promised to call the dealer again. Harvey

 

Ryan,

It just occured to me that you could just unplug the vacuum line from the bypass valve, plug the line with a small screw and have the same effect as the zip tie method, right?