I have a 2005 Mini Cooper convertable and it will accelerate in park but when in drive, will only run 8 mph and will not accelerate. It also does a little surge when driving. I put on a new map sensor and that didn't help. Any ideas on what might be causing it.

 

Sound like it may be in limp mode? Any lights on the dash panel? Our 05' went into limp mode on the freeway earlier this year and it was due to the crank pulley separating (common issue).

 

I don't have any lights lit. What did you have to do to repair, replace pulley.

 

Cooper, non s right?
If so it is an "auto" right...
So it has the cvt....
Ant extra warnings shopwn...like "EP" ON THE SPEEDO?

 

No xtra warnings. Had it checked and threw a 02 oxygen sensor by auto zone.

 

Most common cause of this is a failed crank pulley. See if you smell burning rubber under the hood, or pry on it and see if it moves.
If its broke replace it with the ATI damper so you don't have to worry about it again.
http://www.waymotorworks.com/super-d...ulley-r53.html

 

Okay. We will check it out. Thanks so much.

 

I don't smell the burnt rubber but I will pry on it and see if it moves.

 

If the engine revs but the car doesn't want to move, your transmission may be destroyed. That's what ZippyNH was getting at.

What type of transmission do you have (manual or auto)? Which model (S or non-S)? How many miles on the car?

 

Yup...
A crank pulley damper is exceedingly rare on a non-s (non supercharged) car ..it has a thinner strip of rubber...so failure is uncommon...that and you would be getting lots of lights, an EML , etc...and usually an overheat...
Unfortunately I believe you have a 2005 cooper with a cvt (automatic) tranny...
You seem to indicate it revs in park, but will not move very fast once you put it in drive...
So pretty sure the tranny is toast....

 

That is what it does. Will rev in park but won't rev in drive. It's a automatic cvt. it go's in gear but 8 mph is as fast as I can get. Doesn't slip. But no acceleration in drive. Big revs in park over and over if you mash and let off. You think it's tranny??

 

Yup...
No such thing as slipping on a cvt...
It is a metal BELT and two pulies insider... Sounds like it's stuck. Think of it as looking like a bicycle chain, but with a cone on both ends....a motor moves the cones to change the "gears" aka ratios to change the road speed vs engine speed...yours is stuck...failed.
There was a class action lawsuit over the cvt trannys...MINI provided a settlement to owners.
Was pretty much a disaster...originally MINI said it was filled with "lifetime" fluid...but by 2004, about 2 years after the trannys were introduced, failures started...most dealers started changing fluids regularly...it helped, lots.....
Do a bit if a search...but sounds like your symptoms match..
Cars motor runs fine...car just can't go anywhere....

 

Do you think a filter and tranny oil change would help at this point.

 

The elephant in the room is that your tranny may need replacement. My opinion is that an oil and filter change is a good place to start because there is a chance it may help. If it doesn't work, you haven't spent too much money. If it does work, you've dodged a bullet (replacing the transmission).

Keep in mind that we are just guys on the internet making educated guesses based on not much information. If simple stuff like oil/filter doesn't fix it, you need to have someone knowledgeable evaluate it in person.

 

You will get other opinions in the R50 forums.
https://www.northamericanmotoring.co...k-2002-2006-8/