2006 Mini with just over 40K miles. My EML light and my Service engine soon light just came on. Only thing I have done differently is that I stopped at a local NOCO station, we are in Buffalo NY, and I put about 3 gal of their "Premium" before I noticed that their "Premium" as only 91 Octane. I did not think it would be a problem as I know in certain parts of the country, this is all you can get. Anyways, I have filled up since then with 93 anyways.

The car is surging at low RPM and seems like a loss of power as well. Anyone have any ideas.

I have put a code checker on it and it is throwing no codes.