As I posted a few minutes ago, another problem I have with rebuilding my '02 Mini is the CVT won't upshift. At 20 mph it's running over 3000 rpm and when I punch it to 4000 rpm it just won't shift. I go into the manual shift mode and up or down shifts do nothing. Any advice? Since I replaced the LH axle and lost an unknown amount of tranny fluid (maybe a pint), I also don't know where or how to refill it and to what level. Does anyone know anything about rebuliding these or what internal damage/problem there could be? I know this is a tough one! Thanks

 

well, even a very small amount of trany fluid lost could cause a problem shifting. theres a reason theres a max and min on a tranny fluid dipstick.

 

Let me ask you a question.... Have you replaced the battery in your car? Does it still have the original factory battery?

Some 5-6 months ago, the CVT tranny in our '02 MC with 33K miles started acting up very erratically. It wouldn't either shift or downshift and the car buckled like a rodeo horse in the midst of traffic. The problem would happen at times, then revert, then happen again until the erratic shift pattern became frequent.

Took the car back to the dealer and after a day or so there, the tech discovered that the original factory battery was going and that it was failing to provide the correct voltage to the electrical system and computer, hence causing the ECU to go bananas on the transmission.

The battery was replaced under warranty, ECU settings were cleared/reset and the problem dissapeared! We haven't had any issues since. It appears to be that if you battery is not pumping out enough "juice" the ECU (Liek any other computer) will start sending erratic instractions to the CVT.

The Cooper CVT is the equivalent of a laptop computer on wheels and any little failure in terms of software or electrical current has the potential to develop bizarre problems such as this.

Have the battery checked and replace it if necessary.

Good luck.

 

There is no disptick in the CVT transmission.

 

There's a good reason to have a dipstick, and a fill port, but a Mini CVT has neither! It has very hard-to-access plugs on the sides (3) that may or may not be fill or level check ports, unlike a truck rear differential that only has one and makes it quite obvious. Ánybody else out there got a good idea??

 

hmm.... i dont like the CVT...sounds like trouble


lol

 

You lost fluid, but didn't add any?

Do this right away, but I still think your problem could be electrical related (battery low voltage).

 

The CVT has been good to us But this car is pretty unusual in the way ot reveals certain problems. For isntance what happened to us with the battery and the CVT shifting erratically I would not have guessed in a million years...

 

the whole car is a bag of worms.....i dont even like doing service on my car anymore, its a pain!

 

Good thought on the battery. It was dead when I picked up this car wrecked. Since it's an '02 with 32K miles, that would seem about right. I replaced the battery with a Group 47 from Walmart (I know, I dont like them either, but it was $40 and of the proper size). So it's got a new battery and I would assme it can adequately regulate any slight voltage irregularities...but I may need that checked by Mini (for $99.99/hour service rate). Thanks!

 

One of our local club members is a seasoned auto tech with 20 years experience and plenty hours working on new MINIs. His shop is called Precision Autowerks here in Miami. If you are OK, I can give him a call and ask him tomorrow about how to properly fill fluid in the CVT tranny. This info is of interest for me as well.

 

Yeah have it checked by all means. At least its a start so you can begin isolating the root cause of the problem.

 

Talking to your mechanic buddy would be great! Here's some more background for your buddy; another reason the fluid level is a mystery to me is because I replaced the damaged tranny cooler up front so there was an unknown amount of fluid loss from that,as well as the axle replacement. My shop vaguely told me that there is a fill port on the LH side near the front about 3-4" up from the bottom of the pan. I tried filling there thru a tube but it all ran back out at me. Although none initially ran out when I took the plug out, meaning it wasn't overflowing from there. So I tried filling thru both of the quick disconnect fittings on the tanny where the cooler lines attach (same height as the fill port that didnt work). They also wouldn't take any fluid, so I used a 3/4 oz syringe and force fed it thru one of those two QD lines. About 1 quart...took a lot of squirts! Mini had to fill up a jug of the AT fluid for me because it's not sold by the quart to the general public. Charged me $7.50 for it. So maybe all that will help him decipher where I went wrong. Thanks again!