My son's 05 MCS had the cat split at the weld....the split was so clean I just welded it back together. His car has been stalling quit often lately and idling very erratic. I'm hoping this was a contributing factor.

 

Yes, unfortunately this is a common thing that happens due to the poor quality of the cats from factory. Many people weld the cat for a temporary fix before they buy a new one.

 

One of those unacceptable yet common MINI failures. An exhaust leak under the passenger cabin is serious and something that should be reported to the NHTSA.

https://www-odi.nhtsa.dot.gov/ivoq/

 

Would this have cause the vehicle to stall or erratic idling. Since the repair it's running MUCH better

 

Yup pretty common failure. Make sure the weld has no pin holes or anything leaking it will cause a check engine light.

 

So far the car is running top notch again. No more stalling like it was doing before. I'm still going to replace it in the near future. Thanks for the feed back

 

Same exact thing happened to my '06. $20 welding job fixed it. LOUD before the fix, though.

 

+1 on this experience. I recently had this happen and had it corrected with a weld. I've not been able to find a CA legal replacement, aside from the EO. Does anybody know of a cheaper alternative?