Check engine light after dead battery
 

About a week ago I found the battery of my 98 Boxster completely dead after it had been sitting for 2 months. After recharging the batter the car runs just fine, but the check engine light came on and hasn't faded away after 1 week of a regular 'drive cycle'. Is this coincidence or is it related to the formerly dead battery?

Cel
 

The only way to tell for sure is to check what code you are getting from the CEL.
Most major auto parts stores will let you use one for free. I would think that it is a coincidence, but you have to get the code to find out.