Car is a 2006 Mini Cooper. Non-turbo. Auto. About 30k miles.

Initial issue: Trouble starting. Would tick then struggle to turn over and eventually start. When jump started by cables, would start up right away.

Also, when driving there was a BIG lag in acceleration. As well as every now and then it would do the opposite and drive at really high rpm's. As if it wasn't shifting (car is automatic). Does this at 25-30mph (won't shift until this speed). When accelerating AND decreasing speed. Even when put it NEUTRAL!!!

Solution???
Bought new battery. Car starts without any issue. Changed spark plugs.

New issue!!!!
Now the car ALWAYS runs at high rpm's as described above!!! When sitting, rpm's are normal at 800.

What is the issue? Timing? I know this car is run by electronics for the most part. No engine light or any other check engine lights on. Really feels like it's just not changing gears.

Also thought maybe it could be the ignition coil???

 

Do you have a sport button on this car?

 

No sport button.

 

maybe transmission is going bad? they are somewhat known for it in the first gen MINI's.

 

Sounds like a tranny.....the high rpm while driving/late+failure to shift....
And you gen 1 just-a-cooper (not a insult, just slang for "non s, or NON SUPERCHAEGED" on a gen1....do a quick serch on gen1 trannys....be sure to tell the dealer about the battery issue, maybe you will get lucky and it is a electronic failure on the tranny instead of a mechanical issue....
Good luck.

 

When is the last time you drained and flushed the tranny?

 

The car only 30k miles on it. That's why I kinda threw the bad tranny theory out in the beginning but I will look back into it. Just a weird coincidence that it happened as the battery went bad. I really feel like it's an electronic issue. But who knows at this point.

 

Here's video of what is happening.

1st video is in D
http://youtu.be/pTVdzGgaFX8


2nd video in SD
http://youtu.be/UREBG-xhBms

 

As I understand your SD video you went up to 30, made normal upshift, then let it coast back down. It will make aggressive downshifts in SD mode. In D mode, it is messed up. What about full manual? I assume you can get up to highway speeds in SD mode and it shifts normally, shifting at higher rpms and downshifting somewhat aggressively is normal in SD. So mechanically it is working in SD but not in D so it must be electronics. The control unit or brain box for the tranny is located on the firewall in the cabin about where the steering shaft exits. It has one or two wiring bundles going into it, don't remember which, but I would try pulling them for a couple of minutes, then plugging them back in. Might reset or reboot the box. Pulling the battery sometimes is not enough, still juice being supplied to some components by capacitors. It's worth a shot, I did that to mine when it would not go into full manual and stay there, it would revert to SD. Cleared it up for a fews days, had to do again and haven't had the problem for over a year now. Another item that may have failed is the switch under your gear selector but I don't think that is your problem. Good luck.

This is a S model with a chrono package right? Nothing else would have a rpm and speedo together like that. The plain coopers had CVT's, not very good tranny at all.

 

The chrono pack was an optionon both the s and justa...
And to the op, so we are 100% sure, is it a justa (non s) or an s.
They both got different auto trannys, with different issues.

 

When in full manual, I can make it drive/shift pretty standard.

The tranny brain is right behind the steering column right? Black box? I tried unscrewing it and pulling it down but the steering column was in the way. Had trouble unplugging it. Couldn't get it. Gonna have to try it again.

I tried resetting the ECU but that didn't work either.

 

Mine is an silver aluminum box about 3x3 sitting against the firewall under the dash just above where the steering shaft goes into the engine compartment. Has two wiring harness with a plug each going into right side of box. There is a center tab on each plug that you squeeze toward the plug and pull plug straight out. Very stiff. I am able to pull the plugs without removing the box. Just don't break anything as the box is very expensive.

 

Since it's a CVT, to me it seems like it just requires some "re-programing". We have to do it every time the CVT is flushed or a is worked on. In your case, could be the battery issue triggered a memory fault.

Ya just never know with electronics, sometimes the more complicated they are the more finiky they can be.

 

PS: Dont Mess with the CVT Brain....unless you are qualified tech.

At 30K miles you are DUE for a flush anyways.

Get the tranny flushed and have adaptations done. You should be fine.