Jerky CVT Gearbox

[ar75]

Whenever I pull the shift lever from P to D position, my MINI will jerk, just like another car giving a bumper kiss from rear. The dealer said that it was because I drove between 2000 to 3000 rpm all the time and the computer had programmed my driving habbit. Could anybody help?

[cooper4us]

I would think is normal behavior.

[Sejanus]

Quote:

Originally posted by ar75
Whenever I pull the shift lever from P to D position, my MINI will jerk, just like another car giving a bumper kiss from rear. The dealer said that it was because I drove between 2000 to 3000 rpm all the time and the computer had programmed my driving habbit. Could anybody help?

I do a lot of freeway driving so I'm usually running around 3,000 rpms, but my car hasn't picked up any such computerized habit. It goes from P to D quite smoothly.

[RedBackFur]

My CVT is a bit jerky at stoplights at times as well. Seems to happen when the Air Conditioner is on, which, is all the time since I have the climate control. (usually stops when I turn off the compressor).

It feels like someone is bumping the back of the car. If it is really bothering me, I just put it in Neutral.

My only concern is if it is prematurely wearing out the clutch (Remember no torque converter on CVTs!)

[ar75]

I also worry about the gearbox, so I'll drive my car back to the dealer next week to check it out. Results will be posted in due course.

[kan2]

Hi,ar75
My mini have same problem.
However, I know solution.
This is the defect of a CVT program. The fixing method is making the learned program reset and re-learn.
The shock from N range to D range is disappears by resetting a CVT program.
The dealer should know the operation procedure of computer re-study.
In Japan, many users have solved by this method.

Thank you

[ar75]

Kan2,

Thank you for your information. I'm too busy to get back to the dealer. However, the dealer also told me the problem could be solved by resetting the computer which had learnt my driving habit of keeping the rpm between 2k and 3k. They said that the gearbox would be smooth had the computer been reset but the same problem would appear again if my driving habbit unchanged.

Regadrs

[kan2]

You are right.
Even if it resets at once, there are some persons in whom the again same condition appears.
However, this is the defect of a program. An important thing is the method of re-study.
It is important to be manually in a dealer and to perform re-study correctly not only reset but after that.
This manually memorized process is defined in manual(actually operated MINI).
This study procedure is quite complicated.

[ar75]

To obehave,

The idle is about 900rpm. It's OK, right? My best friend, a service manager of European car dealer, said that the gearbox of my Mini was abnormal. I'm sure that driving a car with the rpm between 2000 and 3000 is a normal behaviour. How come a normal behaviour will bring about abnormal response.

To Kan2,

I would be grateful if you could post more information regrding "re-study". How does it work? Thanks.

[kan2]

The reset method in the tester which a BMW dealer.
1. Diagnose.
2. Selection of function.
3. Service function.
4. Drive system.
5. CVT transmission.
6. Go into a test plan.
7. Original test plan.
8. CVT transmission exchange / study.
9. Reset study.
10. Clutch study (D range and R range 10 times).
11. In-variable-speed ratio study (0-80km running test).

* Reset displays X on the left of a shift position in a speedometer. (X XR, XN, XD)
*?@Go back and forth [ learning a clutch and ] between D range and N range ten time , between?@R range and N range ten times (an in-variable-speed shock improves certainly).
* In order to perform in-variable-speed ratio study, accelerate to 80 km/h first, loosen an accelerator after that, and reduce engine rotation. (About 20 - 30 minutes also of these things are also in this work) .

However, D range shock may occur again for the defect of CVT programming.

[ar75]

kan2,

It's very complicated indeed. By the way, how can you get those information? Have you got a service manual from the dealer? If so, members of this site will be happy enough if you can post it in the forum.

I will get back to the dealer tomorrow to have the gearbox, rattle within the doors and the seatbelt housing and rough idle (A/C switched on) fixed.

[kan2]

To ar75
I'm sorry. I got to know the information on a procedure with mail.
Therefore, I do not know the exact contents of a manual.

[ar75]

I got my car back on 25 October. The dealer said that they had reset the gearbox and it seemed OK. However, the same problem emerges again 10 days later (only 300 km had made). I doubt about the build quality of the car as well as the service quality of the dealer.

Moreover, the dealer also replaced the "steering box", the exact wording they told me, due to oil leakage.

What a "BMW" car?

[kan2]

Is it for only ten days?
Probably I think that it has the bad program which is a basis.
I reset CVT gearbox today.
Later, I will also report here.

[ar75]

Kan2,

How is your baby now? Hope that the CVT is going alright. The service manager of Mini and a senior technician tested the car with me last Friday. They said that they had to check with the manufacturer and the ECU update CD#31 might be helpful to solve the problem. I'm now witing for their reply.

Regards