02 sensor help!

I have a 09 Tacoma with 98k, it just threw at p0031 code. After digging a bit, I’ve come to the conclusion it’s the 02. Bank 1 sensor 1. After searching a lot, I couldn’t get a concrete answer. Is that sensor on the passenger side, under the truck and not the one closest to the manifold? Also, the sensor I have in my cart is Denso 2349084, upstream right. Is that correct? Thank you!!

edit. I figured out the search function on here apparently. Another thread said it is passenger side and sensor closest to the manifold. Is that correct, if so, which denso sensor do I get?

 

If you have a V6, suggest to replace the sensors on both sides.

 

Passenger side closest to manifold.
Best info and source link

https://densoautoparts.com/find-my-part.aspx

 

That’s weird. Rockauto says denso 2349084 is a O2 sensor but denso site says it’s a air fuel sensor??

 

Upstream sensors are A/F
Downstream are O2
The Denso site is accurate.
I can't vouch for the part # you provided.

 

That’s super helpful. Upstream being by the manifold before reaching the cat right?

 

CORRECT
S1 is upstream of catalytic converter and provides data to ECU for air/fuel ratios about fuel trim.

S2 is downstream of catalytic converter. Checks for CC performance by monitoring oxygen left in exhaust gas after hydrocarbons and carbon monoxide is burned off in catalytic converter.

 

Awesome! Thank you so much.