My recent purchased 500E was filled up with a different brand of gas other than what It's been receiving. 30 miles after filling up with this new gas (ARCO premium) the CHECK ENGINE light is latched on. Is this problem related to the new fuel or it is coincidental?
The car has very good service record. The O2 sensor was changed 10K miles ago. Since then it went to the dealer for Dyno test twice. I don't know the reason for the Dyno test but my guess is that it is related to the emission system

Thanks
500E
M5