Hello fellow motorers, yesterday I was driving back home and the service engine light came on. I took the mini immediately to an auto parts store to get a read out and I got this code P2270 with the description: (Oxygen Sensor Signal Stuck Lean Bank 1 Sensor 2). I did some research and it turns out it's the Post oxygen sensor. Some fellow motorers had the same issue and were able to resolve this issue by simply resetting the ECU. I reset the ECU yesterday and the SES light is still there. The mini has 24k on the odometer and only has a 15% pulley, and cai mod . I also had recharged the AC a day before this happened.
Should I go ahead and replace the post O2 sensor or is it okay to clean it with just MAF cleaner. I'm looking for your advise before I tackle this job. Any advise is much appreciated.

 

I would reset the code (with a code reader...your local auto parts store should have one) and see if the code comes back. If it does, then maybe change the O2.

Just resetting the ECU will not remove the code.

 

Thanks Mike, I will try that first.

 

update:
I went to couple auto stores such as advance auto parts and orielys and asked them to reset the ecu to clear the SES light, and they wouldnt do it.
Later today, I called the dealership and they told me if the O2 sensor is faulty, then is covered under warranty. I scheduled an appt for next week to get it looked at.
Couple hours ago, I ran an errand, and Voila! the SES light went off and I havn't done anything yet. If the light does not show up again till my appointment date, then I will just cancel my appointment and motor on.

 

It is a good thing that the O2 sensor is still under warranty.

Just so you know, when you reset codes, it does not reset the ECU. They are different things. Codes are stored in the ECU and can only be removed or reset with a code reader. The ECU reset is kind of like rebooting a computer, you just turn it off then turn it on again. The code memory is unaffected by doing that.

If the light comes back on, the dealer will find what code it is. They will check it anyway when you bring it in for the appointment.

 

If you have a chance invest in a scan gague as you can read and clear codes at any time. Also it will give you various engine readings that the mini doesn't show, such as actual water temp,voltage and other important readings.

 

update:
the light did come back on and go off several times. When was the time to take the mini to the dealership, the light was off. they ran the diagnostic and checked the o2 sensor, and it was it that was causing the light to go off. so they replaced the o2 sensor and cleared the error at no charge. Thanks Motor City MINI, and thank you guys for help.
p.s. i invested in a Scangauge II for future warning lights God forbids lol.