Audi Repair: MIL flashing, staying on, oxygen sensor, autozone

Question
My car has been running great. Then all of a sudden the check engine light came on. It stopped then came back on, then it started flashing and the car seemed sluggish. As I was at a stop light I read to not accelerate to quickly and to stay consistent. This all happened today. I only had to drive it about 2 miles home from work. What could the problem be?

Answer
If everything was fine before, and you are up near 90k miles, this could just be an oxygen sensor failure.  Since you have the MIL, it's easiest to go to an Autozone to get the codes read out so you can get the reason for the MIL to be on.  Lel me know,  Jan