>>>>Sounds like a "Class Action" is in order.
>>
>>I've seen it done before with VW.

That's absolutely correct. My wife bought her Jetta two years ago. The check engine lamp has been on more than off (currently on). After replacing two o2 sensors, MAFS, a trasmission controller update (to fix o2 sensor problems) warranty was extended on a few items. That said, we'll never buy another VW. I hope BMW can recognize this before a happy motoring community becomes terribly bitter.

 

woah - that list is getting loooong!

While it's accurate to say the Yo-Yo is a characteristic to those that have it, it's not relevant because not all MCS's have it. Basically, it's them selecting their phrasing well to seem like they're saying something useful.

Random driving observations: My two MCS's have substantially different throttle pedal feel...as in the throttle pedal to throttle body relationship, or what I'll call the throttle curve. My TD66772 had a perfectly linear throttle curve, whereas my TD76176 has a two-stage, negative exponential throttle curve. This means that my current MCS, when you push the pedal, it has a feeling of "nothing....nothing....nothing... and then BAM, full throttle!" This is highly different than my old TD66772, or any other early-03 and before MCS, which were very predictable, very linear, and basically felt like old cable-throttle systems in terms of throttle curve. Does this mean that MINI implemented a new algorithm in the ECU code? I would guess; yes. Even older Yo-Yo affected (early-03 and before) MCS's have the linear throttle curve. Therefore, there doesn't seem to be a correlation between the throttle curve programming and the Yo-Yo (this is annoying, because I want the old "linear" throttle curve back!)

enough for now..
Ryan

 

I did the zip tie mod and this morning on the way to work my check engine light came on. This is after approximately 75 miles with the mod. I was going downhill and did a quick stab the throttle and then off. The light came on when I got off the throttle. Any ideas why this happened? I plan to cut the tie and get the light reset ASAP.

 

Yes, the CEL may come on with the bypass valve zip tied. I experienced this a couple times, however it is not cause for concern, it's just the computer finally realizing that "something" isn't "stock". The light will go off after three ignition cycles of "normal" operation (which doesn't mean you necessarily have to cut the zip tie), no need to go to the dealer for a reset. I believe the CEL is from the front MAP sensor not reading according to a data table (due to the valve being shut all the time), and this causes a freak-out alarm. Honestly, not a real problem, though the light is annoying

Remember: This is still a temporary "grassroots" fix, and not a permanent OEM solution. Of course, if you want to do either of the fixes, you're responsible for your stuff.

Motor-On,
Ryan

 

Thanks for the info Ryan

 

Just for reference, I've been driving zip tied since 2/10 and have not had one single CEL come on the entire time. Lucky? Or just a damned good job of tying?


Ken

 

>>I'm with MINI USA. An important reminder : Modification of your vehicle or installation of any non-approved aftermarket performance accessory will void the MINI new passenger car limited warranty. Components attached to the vehicle which alter the original engineering and/or operating specifications will void the MINI new passenger car limited warranty. Components attached to the vehicle that result in damage to other original components will also void the MINI new passenger car limited warranty coverage. Feel free to call us at 866 ASK.MINI if you need any further clarification.
>>
Interesting post Mr. MINI USA.... please allow me to take up a bunch of space in this forum with a true, and possibly relevant, story...about 20 years ago when I started at the really big 3 letter computer company, one of my printer ribbon designs was marginal (I would have never admitted it at the time.) Our Service people would stack washers under one of the ribbon spools to extend the ribbon life for customers who only printed a few characters at the beginning of the line...
Anyway… I got really MAD when I found out that THESE PEOPLE were MODIFYING MY DESIGN---- HOW DARE THEY!!!! I'm a fully qualified Engineer how can they possibly do this?!?!?!? I sent nasty letters (on paper, back then) to the service people's managers telling them that they should NOT do this, and the design wasn't tested that way, and Development can't be responsible if something goes wrong etc, etc... Universally, the response I got was "Thanks for your input, but it works, and makes the customers happy". When I explained this to my Manager he smiled and told me to get to work fixing the design....

Well your post takes me back to those days. Perhaps my experience has nothing to do with this situation, but it seems to me that rebuking customers when they discuss how to fix a design problem seems like a sure fire way to **** them off... and, in general, most successful corporations try to keep the customers happy. Perhaps if Mr. MINI USA would be a little more open and honest about what was going on then customers might feel that they were being treated well. As it is, I feel like I have just been scolded by a 2 bit lawyer and I’m not happy about it…. maybe I'm just an old fart with a distorted sense of values.... but my values steer my disposable income….

I would appreciate it if Mr MINI USA would respond with what is REALLY going on,
instead of just scolding us for fixing his/her/thier design problem...

 

Just thought I'd post that my Yo-Yo appears to be gone. I just installed lighter wheels/tires with 1.2" smaller diameter and my Yo-Yo is gone. It was their all the time before during medium acceleration but I tired everything this afternood after installing my new wheels and tires to get it to happen and no more Yo-Yo. I previously had the heavly S-lites with Pirelli run flats. Not sure if heavy wheels and tires may be contributing to the Yo-Yo being worse on some cars and not on other but it seems to have been the issue with mine. I'll update if I find out otherwise over the next week.

 

Everyone has to realize, but not necessarily accept that Corporate greed is in the fore front in this day in age. As I stated above, it is a fine line between running a company to profit and keeping employees and customers satisfied. It would certainly cost MINI $$ to fix the YOYO, hurting the bottom line. It may be MINI's vision is somewhat clouded!

The MINI rep that posts is probably some customer service person that has no real knowledge of really what the higher management is thinking and/or doing and is just posting the pre-scripted lawyer approve responses when they think it may be warranted.

800 customer service's knowledge and helpfulness has been a joke everytime I call. Don't let this customer service poster get you all worked up. It is so ridiculous, how could you all??

 

I've been sitting on my hands on this one, but go ahead and add me to the list.
April '03 Build MCS. Stumble and yo-yo from day one of ownership. Took delivery in May 2003. Stumble solved by v36. Yo-yo still present.

TD68554 04/03 jstines

I was told that MINI is working on a fix for the yo-yo (high level). I hope he lives up to his word...and that it isn't months from now before we have the fix available.

See ya,
JS

 

Super_MINI: This will throw a wrench in the theory: My lightweight summer wheel/tire setup (36 pounds a corner) seems to make the Yo-Yo more obvious than my 41-pound/corner winter setup. How's that for contradiction!

...continues scratching head,
Ryan

 

>>Everyone has to realize, but not necessarily accept that Corporate greed is in the fore front in this day in age. As I stated above, it is a fine line between running a company to profit and keeping employees and customers satisfied.

I am Jack's broken bypass valve.

 

>>Super_MINI: This will throw a wrench in the theory: My lightweight summer wheel/tire setup (36 pounds a corner) seems to make the Yo-Yo more obvious than my 41-pound/corner winter setup. How's that for contradiction!
>>
>>...continues scratching head,
>>Ryan

I suppose it's no more of a contradiction than the fact that some cars have it and some cars don't. Plus I went even further, 50lbs per corner down to 38lbs and reduced the rolling diameter by 1.2". It literally feels like I lifted 500lbs from the car. The acceleration difference Is like I let 3 adult passangers out of the car. I'm implying no more than this is an observation on my vehicle, thought it might help.





_________________

 

definitely - thanks for your input Super_MINI


non-update: no word from MINIUSA yet

 

I removed the zip tie Sunday, the check engine light was too annoying. Ryan, is the stiffer spring the #2 fix you mentioned? I miss the extra torque down low that the zip tie mod added. Any details on the spring you modified? Thanks for the help.
Dan

 

Well well....looks like the yo yo is contagious. I recently tied my bypass just as an experiment to see if I notice any performance gains and I did... a little better throttle response. Prior to the tie mod, I only experienced a brief momentary yo yo once or twice but was not repeatable. After a hundred miles or so, I cut the tie and voila...I'm getting a slight but noticable yo yoing just as everyone's describing. Could the restriction of the bypass movements have caused the ECU to adapt strangely?


aaaaarrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrggggggggggg ggggggggggggggggggggggggg :evil:

 

Sid - the ECU adapting seems to depend on the car. Some MCS's ECU's adapt and make the Yo-Yo worse (like Christian's) and some MCS's ECU's do not adapt, and the Yo-Yo seems to be more mechanical (like mine). You can always do a software reset to erase your adaptive logic memory...

Instructions: Test 19 sub-test 21.0:
OBD II through Odometer

I certainly hope the Yo-Yo isn't contagious! We'd have an epidemic on our hands!

 

Ryan,

Would a reset also alter the powership flash? Electronics is dangerous grounds for me

 

Every time the Yo-Yo Chronicles pops up in 10 Recent Topics, I come over here expecting to see a post about MINI acknowledging the problem and coming out with a fix.

And it still hasn't happened.

 

MSFITOY said:No; resetting the on-board computer has no effect on the vehicles programming; DME or BCM. This means your V36 and/or whatever aftermarket mapping you may have is not changed in any way. Basically: Reset to your hearts content!

Motor-On,
Ryan

 

Now I'll throw a slightly larger spanner in the works. I recently noticed that my yo-yo was extremely minimal if not completely gone. I only realised after reading about these tire swaps that it seemed to disappear about the same time I put my winter tires on. I went with the 15" Dunlop Winter Sport M2's with steel rims. I'm not sure what the weight change was from my stock 16" run flats.

When I first got the car (May production '03) the yo-yo was severe on occasion. I've had v36 done and that seemed to help slightly but it was still pretty obvious. I've actually noticed the biggest difference based on ambient temperature, hot weather being the worst. Since snow tires coincide with cold weather, it's hard to separate the two.

Does anyone know what MINI is focusing on as a fix for the yo-yo? Do they think it's a pure software or will it be like a Ryephix w/ some hardware mod?

cheers!

>>>>Super_MINI: This will throw a wrench in the theory: My lightweight summer wheel/tire setup (36 pounds a corner) seems to make the Yo-Yo more obvious than my 41-pound/corner winter setup. How's that for contradiction!
>>>>
>>>>...continues scratching head,
>>>>Ryan
>>
>>I suppose it's no more of a contradiction than the fact that some cars have it and some cars don't. Plus I went even further, 50lbs per corner down to 38lbs and reduced the rolling diameter by 1.2". It literally feels like I lifted 500lbs from the car. The acceleration difference Is like I let 3 adult passangers out of the car. I'm implying no more than this is an observation on my vehicle, thought it might help.
>>
>>
>>

 

The only leaked info I've heard to date concerning the nature of the fix, is something related to the PCV. I have no idea what the PCV has to do with anything Yo-Yo related....let's hope MINI Engineering actually knows what they're doing!

The "fearless prediction" peanut-gallery (better known as agokart seems to think revised software (i.e. V37) will be "the fix", and it will be released the beginning of autumn. Naturally, this is just a theory - nobody hold their breath!

 

Is there plastic pipe on the vac side of the bypass valve? Maybe it is from the plastic pipe flexing and quickly releasing after the valve opens that causes the yo-yo. Thats what they could mean by "PVC issue".

 

There definitely have been threads about some vacuum hose collapsing and creating a harmonica sound. I thought dealers already had stiffer walled hoses to replace this bugger though. If this was the case, it would seem an easy fix and would probably have already been implemented, especially on cars currently coming off the production line.

>>Is there plastic pipe on the vac side of the bypass valve? Maybe it is from the plastic pipe flexing and quickly releasing after the valve opens that causes the yo-yo. Thats what they could mean by "PVC issue".

 

Oh I have lots of predictions but it seems like they keep updating the computer more and more and more. If it actually fixes it we'll have to wait and see. Now let me look into my crystal ball……