Where should I start troubleshooting? I happened 3 hours after the oil change and the car was sitting the entire time.

 

I think thats an O2 sensor code. Either rich or lean, I forget. First thought would be to check to make sure the sensors are plugged in and not damaged or something from the outside.

I would unplug the battery, let it clear, and see what happens.

 

P0172 System too Rich (Bank 1)

that is what i found in the OBD II codes for these cars

 

I found a tear in my CAI silicon housing. One of the causes can be a vacume leak etc. I haven't fixed it yet but i will let everyone know if that is it.