I had been seeing a random CEL for the last year. The dealer pulled the code for me and said the left rear oxygen sensor was bad. I finally decided to order and replace the bad oxygen sensors. Getting the sensor out was not difficult but pulling the wire out of the socket and out of the bracket was a pain the rear! What I really find interesting is that even though the exhaust was cool to the touch the transmission was still hot, 3 hours after sitting. Sorry no pictures. Project took me about 30 minutes. So far no CEL light!

 

I would think the tranny was hot due to transmission fluid being present - the exhaust is empty and can cool quicker.

 

What kind of sensor did you buy? OEM?

 

[font="'Comic Sans MS"]any change in fuel consumption?[/font]

 

I bought the sensor from www.bavauto.com for $150. It was a bosch sensor that was an exact match to the one I took out. As far as fuel consumption I have only run one tank through and my mileage went up 1.3 mpg, but i only replaced one of the four sensors in my car. I may replace the other rear one on the passenger side and see if it makes a difference.