'03 CR-V O2 sensor problem

The check engine light on my wife's 2003 CR-V turned on about a week ago. Using Autozone reader I got the following codes: P1166 and P0134. After some research I found out that this has something to do with O2 sensor (A/F in Honduh speak). P0134: 02 Sensor Circuit No Activity Detected (Bank I Sensor 1), and P1166 is also something about the O2 heater circuit. My questions are, there are two of them so how do I know which one to change? Changing it looks easy enough, will I need a special O2 socket or will a regular socket work?

I know it's basic question for most here so as a NOOB I really appreciate your input. Thanks all.

According to the a CRV forum its part #15 on this diagram.

G_Stock wrote: According to the a CRV forum its part #15 on this diagram.

So it looks like the upstream sensor. Thanks man.

Yep, bank one means the upstream one.

iceracer wrote: Yep, bank one means the upstream one.

Dang, I called a local Honda dealer and the price for the O2 sensor was $373..man talk about expensive parts for Honduh...I'll probably try to get it online or from local Advance/PepBoys/Autozone.

In reply to ea_sport:

Try RockAuto.com, I had to get one for my wife's 2003 Avalon. Autozone wanted $300 for the Denso (O.E.) unit. Rock auto had it for $120.

I just checked, $163.79 for the Denso unit there.

Did one of these for my Dad's CRV a couple years ago ('03, 85k or so when it threw the same codes yours is now). The dealer wanted $350 and I got it from either RockAuto or PartsTrain for about $150.

G_Stock wrote: In reply to ea_sport: Try RockAuto.com, I had to get one for my wife's 2003 Avalon. Autozone wanted $300 for the Denso (O.E.) unit. Rock auto had it for $120. I just checked, $163.79 for the Denso unit there.

Thanks, I found it too. Is there any non OE unit that I can get at places like Advance/PepBoys/AutoZone? I was planning to do it this week-end and if I buy the part online I'll have to wait until next week-end to do it. Thanks all.

Almost any of those should have it.