Let’s not over look , it could be as simple as a battery lobotomy, now that’s pretty easy! All you need is a 10 mm open box or combination wrench to remove the negative cable from the battery, it lives back beside your spare tire under the trunk mat , disconnect it for 30 minutes. Reconnect it and see what the CEL shows.
Your PCM lives under the front hood in the drivers side, there are black plastic covers to remove, it’s really not that complicated just follow simple steps

https://www.flashmastersecm.com/prod...in-ecm-pcm-ecu

 

Copy that i can easily do that, i really hope that fixes it so i dont have to use money when i dont have to right now

 

Keep It Simple Sam , (originally another derogatory name for lack of intelligence) start with the easy to check cost effective things. If it’s still broke move on to the next step.
But if you throw parts at it , you might be surprised, it’s still broken!

 

Im a complete novice when it comes to cars so i brought it to a mechanic and thats what i wqs informed of so i came here for ideas and easy fixes

 

You would get better guess at a Cobalt group, HHRs were not made in 2005, so we are just guessing generically.