Well this code popped up last night in the pending status. I saw the TSB #01-031 about this code possibly being either the "Primary O2 Sensor" or the ECM needs to be replaced.

I reset the ECM as I also read that it could be a false code. If it comes back I will prob. replace the O2 Sensor first and then go from there.

My question, which is the Primary O2 Sensor and where is it?

Also Honda wanted $248.00 for this thing. Autozone stated $100.00 Big difference.

The primary O2 sensor is shown in the link here (http://www.hondaautomotiveparts.com/auto/jsp/mws/prddisplay.jsp?inputstate=5&catcgry1=ACCORD&catcgry2=2000&catcgry3=4DR+EX+LEATHER&catcgry4=KA5MT&catcgry5=EXHAUST+MANIFOLD+%281%29) for $115.62. You can do it yourself quite easily. You'll have to buy/rent an 02 sensor removal tool though. It's a good idea to spray down the sensor with PB Blater or something like it. I think it's also best to get at it while the exhaust is still warm.

Thanks for the photo. As for the tool, it looks like I might be able to get at it with vice grips. All in all, I will prob. buy the sensor and have a local mech. put it in.

Can't take but 15 min. tops.

You pay to rent the tool, but when you bring it back they refund your money. It's basically just a deposit. I highly recommend using the tool versus a vice grips. Let it be said "the right tool for the job". If you're going to have a mechanic do it then no worries.