2009 Aveo Bucking/Jerking/Losing Power

[CKTofu]

I recently bought a 2009 Aveo with just over 64000 miles, had it tuned up and the thermostat and timing belt replaced. It was fine for a while, then has been having the same issues as many of the others above. Randomly, it loses power, "bucks" or picks up speed unexpectedly. Most often, I have to turn it completely off and restart- then it drives fine (for a while) There is no rhyme or reason to this issues, sometimes it's fine for a 100 miles, sometimes just a few. Any ideas? Thanks!

I had to replace both my O2 sensors, as I mentioned in a couple posts previously. However, before blindly replacing parts, any chance you have an OBD2 reader you can use? You can get Bluetooth ones to use with your smartphone if not.