O2 Sensor - Upper, Installed

When someone says that you need a 22mm O2 Sensor Socket to change the Upstream sensor, you should probably listen, unless of course you want to dissassemble half the engine instead of spending the $10. 

"White Brass" is not a desirable color.

This next pic will give you a good idea why you need an O2 Sensor Socket and a 10" extension

Looks accessible right?  It took me 10 minutes to get a clear shot of the sensor nut

                     It's down there     |         ....  really...
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