If still under warranty, I'd have the dealer re-look at it.
I went in for an oil change and asked them to check for leaks for me and stuff because I had this re-occurring CEL. Well, they said things were "fine". Got the CEL the next night.
I cleared it by resetting my ECU and it hasn't returned since. 
I went in for an oil change and asked them to check for leaks for me and stuff because I had this re-occurring CEL. Well, they said things were "fine". Got the CEL the next night.