2000 4Runner SR5 2WD - Oxygen Sensor replacement to clear P0135/0141

Just replaced both oxygen sensors on my 2000 4Runner SR5 3.4L 2WD (non-California) after research here, YouTube and the interwebz and found conflicting information. Some sources suggested that the upstream and downstream sensors are identical but that is not the case as the required electrical leads are different lengths. Here’s what you need:

Denso 234-4162 (upstream)
Denso 234-4161 (downstream)
12mm combination wrench
Flat head screwdriver (to remove connectors)

Here’s what you’re taking out:

Here’s what you need:


Replacing these cleared codes P0135 and P0141. If you have the right tools and parts, it should only take maybe 30 min to do both. The nuts on both the old sensors were pretty easy to remove but some penetrating oil might be helpful to some. Hardest part for me was releasing the upstream electrical connector due to my fat hands. Can’t say this will work on anything other than a 2000 SR5 3.4L 2WD. Good luck!

 

I would still recommend people to call the TOYOTA dealer with their VIN. The parts guy will look it up and give you the EXACT part numbers you need for your car. Then you can cross reference it to DENSO if you don't want to buy from the dealer.

 

Thanks, I got this info from the Denso website.