Did you ever figure out what needed to be changed? I have the same error message. I was told that my MAF sensor may be the culprit. I would just hate to buy a new $200 MAF sensor just to find that the error doesn't go away.
I connected my scan tool, and some of the errors that it pulled are:
27C3 Thermal Oil-level Sensor (don't think this is related)
276D Function check, Tank Ventilation
2882 Fuel Trim, Bank 1
2883 Fuel Trim, Bank 2