Transmission not engaging on cold start

[msofty]

Hi everyone,

Bought a used 2004 Mini Cooper (CVT), 113,000 km on it.. been fine for the past few months. Noticing recently that on cold starts it's doing something strange transmission-wise.

Basic problem:
- On cold start, I go to engage the transmission to go into reverse. It goes into reverse, RPM's rise, but the transmission doesn't "engage". If you go to Reverse, Drive, Neutral, SD, nothing engages.
- If you then turn the car off, then back on, sometimes it will do the same thing (go into gear, but do nothing), other times it will engage right away
- It only happens on cold starts (car off for an hour)
- If it happens, and I do a cluster reset through the odometer (using the FAQ info here, thank you mini2!!), on immediately following start it always works and never exhibits the condition.
- The other option, if it's doing it, I pull the parking brake up a bit, put the car in reverse, and accelerate slowly. It will then kick slowly into gear (a bit of a bang, so guessing that's not a good thing).
- Hooked up to an OBD2 reader, there are no codes of any time, when it happens and when it doesn't.

I spoke to Mini service about it, and they had a few thoughts on what it could be. They said they wanted to run a diagnostic ($, similar to the OBD?) and if there were no codes, they would do a transmission flush. The last flush was at 98,000 km and Mini says they don't usually do it until 130k again. The only thing I can think of is that the previous owner let the transmission leak a bit, and that it needs to warm up a bit until the fluid expands. Being a closed system I can't check the fluid level easily (or can I?)

The guys at work who are also mechanics checked that my brake switch fuse was not out, and we examined under the CVT cloth to see if the mechanics look okay. Visually they seem fine.

At this point I'm tempted to pay the $300 and get a transmission flush, but before I did I wanted to post and see if anyone else had any thoughts on what it could be. I should mention the CVT is smooth/works fine once this condition clears, and that otherwise the car runs very well. I also tried putting cardboard under the car and there is no fluid leaking of any kind.

Anyone have any thoughts?

Sorry for the long post, but I wanted to get all the variables so those who are far more experienced than me could give me some ideas on what to look for.

Thanks!

Mark

[msofty]

Thought I'd give everyone an update on this in case someone else has the same issue.

What I tried:
1) replaced the battery. Car itself started acting better, but the issue persisted
2) Had a voltage test done from battery to ignition. All clean.
3) Had a computer diagnostic. No codes
4) Did an ECU flash to the latest Mini dealer provided ECU. Car drives better (smoother) but issue persisted

Finally, after an oil change, I saw some fluid on the ground that turned out to be transmission fluid. I had Mini check it on Friday, and it's the transmission cooler that's cracked, slow leaking fluid, and there are cracks in the lines to the cooler. This is causing both transmission fluid to leak, and for decreased pressure in the transmission. They suspect that this is what is causing my transmission to not engage on a cold start, the pressure takes time to build up. They also found about half of my fluid missing from the closed system, which they are flushing.

Moral of the story: If you find that your transmission is not starting on a cold start, start with the battery, then check your transmission cooling (fluid) system.

PS: This type of repair (cooler, adapters, coils, etc) costs $1300 or so, of which $850 is parts and ~$300 is labour.

[msofty]

Recognizing that I am replying to myself... but... figured I'd share the final result here.

So, after the transmission cooler was replaced by Mini Downtown (which, btw, I STRONGLY RECOMMEND AGAINST using Mini Downtown in Toronto. They are extremely rude, the manager there Justin is not helpful, he is abrasive, angry, and doesn't like helping customers; they forgot to clean the underbody of the car, and it leaked residue all over my condo garage. Returned, was cleaned up, and I started driving it again), the problem persisted. The cooler replacement did NOT fix the vehicle despite Mini Downtown's insistence that it would.

Recently, I finally had enough and took it to a different dealership. For $110, they did a full diagnostic, checked fluid levels, end to end check of the car, and they decided to perform an adaptive reset (done by them hooking up to the ECU and issuing an adaptive reset) on the transmission. The car now drives beautifully! If you are in the Toronto area, I strongly suggest Mini Vaughan for your service. They treat you with respect and they don't try and charge you for unreasonable things. Mini downtown argued they had to always charge me to check the fluid level in the transmission, even though Mini Vaughan did those types of things for free, and even though Mini Downtown had just done a repair of that very same component. Stand behind your work, Mini Downtown, or you lose customers. This customer is definitely never going back there. Vaughan won by business.

One comment for those who may think I'm being unreasonable. I called Mini Canada and spoke to them about what happened. They advised me to try Mini Vaughan as they get complaints every day about Mini Downtown. So, at least know I'm not alone!

If you have a 1st generation R50 with transmission issues, I strongly suggest you always check the following things:

- Check your fluid level. This is the #1 thing I'm told that can make a transmission act strange. When they refill it, make sure the fluid comes out clean - if it is, it's an indicator of a healthy CVT
- Battery Voltage; if your battery is very old, replace it. Transmission needs a good strong charge to engage properly
- Latest flash of your ECU. Make sure you are up to code.
- Check your cooler. If the pressure is low, it could explain your issue. I definitely had a leak, but it wasn't what caused it
- If you are not the first owner of your R50, and it's many years old, try a transmission adaptation reset (known as a "drive cycle"). It learns over time how you drive, and if you dramatically change your habits, and especially if you do transmission work (cooler replacement), a drive cycle seems obvious. Too bad it wasn't obvious to the dealership I paid so much money to!

Happy driving,
Mark

Quote: Originally Posted by msofty (original)

Thought I'd give everyone an update on this in case someone else has the same issue.

What I tried:
1) replaced the battery. Car itself started acting better, but the issue persisted
2) Had a voltage test done from battery to ignition. All clean.
3) Had a computer diagnostic. No codes
4) Did an ECU flash to the latest Mini dealer provided ECU. Car drives better (smoother) but issue persisted

Finally, after an oil change, I saw some fluid on the ground that turned out to be transmission fluid. I had Mini check it on Friday, and it's the transmission cooler that's cracked, slow leaking fluid, and there are cracks in the lines to the cooler. This is causing both transmission fluid to leak, and for decreased pressure in the transmission. They suspect that this is what is causing my transmission to not engage on a cold start, the pressure takes time to build up. They also found about half of my fluid missing from the closed system, which they are flushing.

Moral of the story: If you find that your transmission is not starting on a cold start, start with the battery, then check your transmission cooling (fluid) system.

PS: This type of repair (cooler, adapters, coils, etc) costs $1300 or so, of which $850 is parts and ~$300 is labour.