An OBD realtime data stream reader might be a big help in diagnosing that bucking. It would enable you to see if the fuel trims are changing at the point the bucking takes place, and (if they are) if the trims are showing rich or lean. And you would also be able to find out if any misfires are being counted by the ECM. The Torque app for Android is a popular and less expensive choice, or there are readers available off the shelf as well.

Also just an FYI that in 2009 the second gen Aveo began using COPs, and that's what that recall is for. So your 2008 could not be included in that particular recall.