The plug on the o2 just has a clip and pulls apart. Be sure to put a little anti-seize on the threads of your new plugs, and your new 02 sensor. Be carefull not to get it on the other parts of the spark plugs, just th threads.
6" extension and 5/8" spark plug socket.
O2 is a7/8" O2 sensor socket.
Your second o2 sensor is down under the car in the exhaust pipe right behind the catalaytic converter. Probly right about at the front of the seats, maybe a little farther forewards.

 

i would check your headgasket.....if its cracked it could be leaking engine coolant....which burns white......seen the same thing before

 

And how do you do that, besides pulling the head...at which point you would replace it anyway.

 

The head gasket works just fine. There are no signs at all of gasket leaks.

I am going to change the spark plugs, upgrade the wires (I am going to have OEM ignition wires for sale this weekend - less than 2000 miles on them), and replace the pre O2 sensor. Hopefully that will solve the issue.

I also noticed that the car might need new rear struts (I am hoping it might be just the bushings).

 

Keep us updated.

 

Alright! I was finally able to change the o2 sensor (after an hour and a half of work - thanks to my cheap tools).
The car is working perfectly now! Power is back, no stalling, no hesitation, thank you all!
While I am there I noticed that the vaccum hose going to the throttle body is split in half, I changed that too