Which O2 Sensor do I need
 

Bank 1 Sensor 2
Manual (R3 Edition)
P0037

The wire ripped off my old one...lol :D:

I know there is a difference between the manual and auto, and it's causing me confusion.

Is this it? Autozone wants about $250, I was hoping to find it at Amazon for less, but I want to make sure I get the right part. My inspection is due before the end of February too..ugh

https://www.densoproducts.com/product.aspx?zpid=26993

You need the rear O2 sensor in the cat, right?

2005 MAZDA RX-8 1.3L R2 Oxygen (O2) Sensor | RockAuto

Any of these labeled "Downstream" will work (depending on your transmission). NTK (NGK's O2 sensor brand) is probably the safest bet.

If you really want to buy from Amazon, just plug the part numbers from Rock Auto into the Amazon search field.

For peace of mind, avoid any of the "universal" type sensors because they don't have a connector on the pigtail and you have to splice your existing one onto it.

I got super lucky on a pricing mistake on Amazon and picked up this for only $68, with Sunday shipping.

https://www.amazon.com/gp/aw/d/B007MD2D30/ref=sr_ph_1?ie=UTF8&qid=1487629408&sr=sr-1&pi=AC_SX236_SY340_QL65&keywords=denso+dac234-4278

My mechanic took about 5 minutes to install and the light immediately went off. After looking at the old sensor, I probably could have fixed it...One of the wires was completely stripped off and seemed reparable. He was against it so I just changed it.

Drove about 6 cycles so far and no issues.

Thanks!
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