I have a 2002 Cooper S. The front O2 sensor was replaced 2008 at my expense. The catalytic converter was replaced under emissions warranty 2/09. Now the check engine light is back and dealer says the back O2 sensor needs to be replaced. According to dealer the extended warranty only covers cars produced 10/03 to 11/06. I've tried to read all the related posts and have several questions:

What was the original warranty for the O2 sensors? I've seen 80k/8y mentioned, but don't know if this is accurate? Because if so the front sensor should have been covered before and car still has less than 70k miles.

When the catalytic converter was replaced, should the rear sensor have been replaced then?

Anyone know why Mini wouldn't have covered the 1st year of production in this warranty extension?

 

I know that the 05+06 mini's had the o2 sensor extended to 10 yr or 100,000 miles due to "duribility issues with o2 sensors. Call the dealership and ask. Maybe the older ones were effected, or the one installed was from the bad batch....just like the 05+06's.

 

I recently bought an 06 MCS and the service engine light came on. The dealership here in Sioux Falls, SD turned the light off and informed me it was an 02 sensor. Since the agreement was that I would take care of the sensor, I made arrangements to drive the car to Bloomington MN. 287miles one way. The service person took the car in and about an hour later came back to me and said we have a little problem. I asked, what's the problem? He said that when the dealership in my town turned off the light without having the right diognostic computer, they erased the history of defaults. Therefore they couldn't diognose the problem and BMW won't reimburse them for warranty work. I was really upset and went back home, another 287miles. Anyhow I was told to wait for the light to come back on and bring is back. I did and all is well. My on the road gas milage for the first trip was only 21.9 miles a gallon. After the replacement of the 02 sensor the gas mileage jumped up to a respectable 29.7. FYI