Pooh Man, Strange as it sounds, I found the O2 sensor, but it looks like it takes a special wrench to remove it if the cap does not come off the top of the sensor. What kind of tool does one use to remove and replace the sensor? I had an 2009 LT here in KC out for a test ride so i was only able to eyes on the sensor.If i do change one, is aluminum anti-seize gel used on the threads? When I do get an Aveo, at least I will be able to do basic maintenance. Thanks for your time!