Software Update v38 = Yo-Yo is Gone!

Here's a welcome email that arrived in the MotoringFile inbox this past weekend:

I've been testing MINI's latest ECU update (probably will be known as v.38) on my “yo-yo-ridden” 2004 MCS for 538 miles and have yet to be able to provoke its return. This latest update finally appears to cure the yo-yo. It is due to be distributed to MINI dealers in June.

My ECU was sent to MINIUSA in Montvale, NJ last Monday(5/10) for reprogramming and was back in my MINI on Wednesday (5/12). New County MINI in Hartford, CT worked with MINIUSA to make this happen with an impressive level of customer service.

Since then, I have been putting the MCS through its paces with various engine loads (throttle position, weight, A/C draw, etc.) and gear selections in an effort to determine the success of the update. The final test was a roundtrip from MA to NYC. Quite simply, the yo-yo is gone.

In addition, the new update has not induced any “regressive” behavior: no stumble, no cold start problems, no A/C issues…nothing. Needless to say, I am now one happy camper!

Please pass on this exciting information to the MINI community as well as my gratitude and admiration for the superb efforts Ryephile (and others) have made in working with MINI to effect this long-awaited solution.

Sincerely, Theo Matthias

We at MotoringFile would also like to pass on some major “props” to Ryan (Ryephile). In fact Theo himself said it best on a MINI2 thread; Ryephile handed the fix to MINI on a silver platter and probably cut months off the time it has taken to release this “True Phix”!” We hope to have further word on v38 soon.

  • Tim in MD

    Does anybody have a sense of when these updates hit the factory? I'm curious as to whether my MINI, which started production on 27 April, will have the latest software or not.

  • MINI will update your car to the most current software version when it arrives at the VPC.

  • Theo

    Typically, the late-breaking ECU updates are done at the VPC when your MINI arrives in the US. If this update unfolds like v.36 was rolled out, there is a very good chance that the VPC may have it already. Thus, there is some reason to be optimistic.

    If not, you should not need to wait for it very long as it is scheduled to be in MINI dealers' hands toward the middle of June.


  • mike pisto

    does any one know if this will fix the herky jerky of the CVT at the 9 mph mark?

  • Frank

    “does any one know if this will fix the herky jerky of the CVT at the 9 mph mark?”

    No it will not. This is a charactheristic of the CVT transmission. The “yo-yo” is a MCS concentric issue and has nothing to do one with the other.

  • So If I had no problems (AC, Yo-yo, stumble etc) Should I still request this update?

  • Theo

    Michael S. –

    I think Ryephile will back me up when I say:

    “If it ain't broke, don't fix it!”


  • sid the squid

    this is the first that I've heard about AC issues. Can someone point me to info?

  • GJR

    I'll believe this actually does what it says it does when it works on my car. I have a 2003 MCS with a stumble, and I had V.36 installed three months ago (which was supposed to remedy that), but the stumble's back now with the warm weather 🙁 I have seen many posts from other people having the same issue recently on NAM in the “under the bonnet” thread.

  • Ryephile

    Theo is right on the mark, there's no need to get V38 if your MINI is already running like a champ!

    Thanks Gabe for the props! (grin)

    Cheers, Ryan

  • Trevor

    Hi all-

    I'm new here, but have been checking out the site for about two weeks now. i take delivery on an 04 MCS tomorrow morning (5/29) and I'm wondering: how do I determine if v.38 was installed at the VPC already, or if I'll need to get my car back to the dealer to have the ECU sent out later?

    thanks in advance, and I enjoy the site a lot – it's made the wait for my car educational instead of just plain punishing!

  • Mark


    How is v.38 holding up for you now? I saw some of your other posts (I think MINI2?) It didn't sound like you were too happy with the tach lag, etc. Do you think the benefits outweigh the detriments? My '03 MCS has always had the yo-yo, but I have to say in the last few months I've noticed it less and less. Now I only really notice it under a load (i.e. pulling away up an incline or with the A/C on). Just wondering if I should go for it or leave as is. I was thrilled when v36 got rid of my stumble. cheers, Mark

  • Gilbert Cabral

    I went to do my 25,000 mi. sevice that I ask my dealer to intall the V38 software. Today I picked it up and my car is a champ …. The stamble is gone the hicap is gone also the pinging is gone, not only that I also requested if there's fix on Harman Kardon stereo, they also fix that(speed volume control) it's work….