Originally Posted by
kourt78
Maggy55, I have not checked for any codes, I don't have a OBD reader

I realize it's a pretty broad question,
I was just praying for a simple explanation or idea! 
Take it to a dealer. Happy now? Pretty simple idea.
Look, it the basic list (which leaves out a lot of exotic stuff) has over 390 codes. You want us to GUESS which one, based on
"I have a 2005 with 128K miles... the check engine light came on for a brief period while driving and then went off within the day. Check Engine light unfortunately returned and has now been on consistently for a few days. She's driving just fine.."
We get this from people on Facebook as well as here, every day. You are not alone - but please, you have a light that TELLS you the ECM sees a code or code - why not READ the code and give THAT to us? THEN we can help.