This info comes from a long time reader of the site:
“I spoke w/ someone at BMWNA today regarding the stumble in the MCS. He told me that the fix they are loading on cars now may, or may not, become software version 36. He also said whatever software version 36 is, it may be out in a couple of weeks or maybe not until near the end of the year.ÂÂ
Regarding the yo-yo, he said that the current fix is purely intended for the stumble, it was not intended to address the yo-yo. He said that neither he nor several of the test engineers have ever been able to reproduce the yo-yo. In other words, there is no fix in the works.  This being said, he commented that some owners have sworn to him that the yo-yo went away when they had this stumble fix loaded. Who knows, maybe they are linked. There are so many variables being fed into the software it's hard to tell what effects what (my thoughts, not his).
He explained that the stumble snuck up on them this year. They did not experience it last year, and it was definitely more evident in the hot states. MINI sent engineers to the SW and Fla. to come up with this fix. Interestingly, he commented that they really didn't know about the problem until they began reading more and more about it on the various MINI forums!! The fault was not initially brought to their attention through the dealer networks, but rather through these forums. I actually see this as a down side to the forums. It seems that a lot of folks checked the forums and said, “hmmm, there's not a fix I'll just wait until there is”. I did this at first but then realized, this doesn't get the info back to MINI. I urge everyone as much as possible to let your dealer know! People still post daily that they went to see their dealer and their dealer had never heard anything about the stumble.”
Analysis
Certainly interesting news, thanks. Lets hope this is indeed the fix that everyone has been waiting for.
<p>I have a late September (9/26/03) build '04 MCS with 514 miles. I have not yet experienced the stumble but I do have the yo-yo. Perhaps mine was loaded with the V.36 software at the VPC before delivery to my dealer. If this is the case…the yo-yo still lives.</p>
<p>Any way to tell ECU software version number? Is it hidden in the OBC test mode?</p>
<p>Theo</p>
<p>I'm just learning of this stumble and yo-yo issue and trying to research backwards with regards to the description. </p>
<p>Back during the warmer months I recall my MCS having issues at the first crank in the morning. It would frequently start…then stop. Then I'd recrank. Frustrating to say the least as I was always used to the car starting right up and continuing to run. Odd I thought and did not know how to correct.</p>
<p>Several other times, I noticed after turning into a road with a small incline, the car would lose power being in second gear as I began going up. Pressing the gas pedal did not introduce any more power, and then all of a sudden, a big thrust would happen. Is this the stumbe that is being referenced?</p>
<p>Anyway thanks for any help on describing the stumble and the yo-yo. Now with the weather cooler, it appears the car is ok. I am in Atlanta.</p>
<p>Elmor,
Your car starting & stalling is what the forums call “cold start”. It seems to be related to the “conditions” being different than when the car first learned how to work!?</p>
<p>I received my car in Feb; I had cold start issues during the summer; now with cooler weather it starts fine again.</p>
<p>Your description of losing power in a turn might be related to DSC … if you can repeat it, try it with DSC turned off.</p>
<p>My understanding of the stumble is that the engine loses power during initial acceleration from stationary. I have not experienced this except when the a/c is turned on.</p>
<p>Unfortunately when you DO tell your dealership's service department about it they tell you that you don't KNOW HOW to drive a stick. So why attempt to report the problem to someone who chooses to BELITTLE one's driving skills. This happened to me as well as to other MINI owners at the MINI North Scottsdale location. I reported it to them just after taking deliver of the car in Feb 2003.</p>
<p>Dominic – I completely understand your situation. I've heard of service managers simply refusing to believe customers. Obviously the good ones do believe them and take it to the next level. But for every great service department there is at least one bad one out there. </p>
<p>Personally I've experience the occasional stumble (w/ DSC off mind you) and am looking forward to a fix. Granted it much more pronounced with air on or in hot weather so I haven't felt it in quite awhile.</p>
<p>Bravo for MiniNA. I'm impressed that Mini addressed an issue only addressed to them in the online forums. I could see this as being a issue that no one dealer would recieve enough feedback on to think that it was more systematic and not specific to just one car or one customer's driving style. (I'm not excusing Dominic's dealer's dismisive attitude – shame on them.)</p>
<p>I'm glad to see Mini taking the initiative in seeing and (even better) addressing what their drivers actually say about their cars amoungs themselves.</p>
<p>In the spirit of “Continuous Improvement”, MINI should instruct their Service Advisors to review the various forums. Alternatively, MINI should send a “digest” of the key forum issues to their MAs and SAs so that they don't appear to be “uninformed” when speaking to potential sales and service customers.</p>
<p>I know it boils down to dollars. If MINI sanctions a dealers effort (labor) for investigating a potential problems, then MINIUSA will have to reimburse the dealer for the labor. </p>
<p>By contrast, my '00 328i was beginning to make a noise in the front suspension when turning. The dealer recognized this as a known A-arm problem and replaced them on the spot. Seems like it should be that easy.</p>
<p>Theo</p>
<p>The variation of the stumble between cars must be enormous. On my car, there is simply no way one could put it down to driver error. The sum of ground speed, engine speed, and clutch release speed, followed by a severe hiccup just in the last split second before the clutch is fully engaged in first gear just don't add up. It's obvious that the engine is cutting out. How anyone (i.e. a dealer) could drive my car and not say, “yeah you've got a problem”, is beyond me.</p>
<p>I'm hoping this is really the fix. Now if they could do something about the yo-yo.</p>
<p>I just got my min a month ago,after putting a 1000 mile I observe the same others have stumble and yoyo I bring it back to the dealer and they say that they need to load the sofware,I drove out and the same problem,I call back and say that the same problem the answer is “you are joking” I said I'm not joking of expending $32k on this car that lose power and dance,remember we are in ca. LEMON LAW ca be applied.
By the way anybody have aproblem of hamon kardon stereo, this stereo should adjust the volume while you are driving in certain speed they call it speed volume adjust it is in the manual but mine does't work the dealer said they don't have that in this car.</p>
<p>The software that fixes the stumble will not reach dealerships until late November or December so most likely anything that your dealer would have updated your car with wouldn't have solved the issue. I would recommend waiting a month or two and then calling them back.</p>
<p>I'm pretty sure H/K does have volume control like the standard MINI stereo. This can be adjusted by holding down the music symbol button on the stereo and scrolling through the menu accordingly.</p>
<p>yes, you are right but what i am saying is, there should be an icon saying speed volume control ( check CD manual MCS)this SVC should increase the volume of the stereo depend on speed of the car.</p>
<p>After 5-6 visits to Knauz complaining about the hesitation, yo-yo idol, surging, and stalling issues, they finally came through and had new software installed by a MINI technician on October 22nd. I have a June 2002 build MC with the 5-speed.</p>
<p>The software has made a huge difference with the car. So far (fingers crossed), none of the issues have reappeared.</p>
<p>As of the day of my appointment, this software had not been released to the general public as MINI was awaiting EPA approval. Unfortunately, I don’t know the software version number, nor did the service advisor. The service advisor did mention something about this software addressing the issue of summer and winter types of gasoline.</p>
<p>About the upgrade… Initially after the software update, the car had a rough idol at stops (compared to normal) and the gas mileage dropped into the low 20’s. After a few days of driving, the idol returned to normal and the gas mileage has been improving. My MINI now drives like a “normal” car without the hesitation on acceleration.</p>
<p>Sorry I don’t have more details, but I moved last week and am still recovering. :)</p>
<p>What is a 'YO-YO'? Please someone give an explanation.
I know about the stumble, my 2003 MCS does it. I went to the dealer and they did not know how to fix it and just said nothing wrong.</p>
<p>i just had my car in for some warranty issues, namely my glove box latch not working and the dreaded stumble. they sent my software back to new jersy to be updated as the dealer (assael here is southern california) did not have the series 36 yet. i was without the car for 4 days which annoyed me but the stumble is largely gone. 🙂 june 27 2003 model. i'm hoping that by the time i return for my 10,000 the #6 software will be perfected and available to the dealers. the car is much smoother through all of the gears and does gag in first when starting out.</p>
<p>my cooperS got a problem just like what you guys saying, as far I investigate and making the dealer pest off they installed the new software but still have the problem,untill I make a mistake putting a gas unleaded 87 remember guys this car will ran at 92 octane or better and we only have 91 octane. Have that kind of gas here guess what, the car dances like he needs more alcohol, that’s why maybe the version 36 will be in placed and installed. By the way if we read the manual saying that the car have the motor driven accelerator that don't have the any cable except wire to it, that this prevent from unwanted air to gas ratio in which affect the smog or unburned gas.
Check it out cpu of the car is made by siemens and siemens is BMW the are mandated by German Government to clean the air.</p>