Hey everyone,



I’m having some trouble figuring out which oxygen sensor is Bank 1 Sensor 1 on my 2017 ES 350. I’ve looked at a few schematics and posts, but I’m seeing conflicting info and pictures.



Also, is it safe to assume I should go with an OEM sensor for replacement? I’ve never done this repair before, so any tips, links, or helpful videos would be greatly appreciated!

I’ve determined it’s the O2 sensor from a OBD scan at AutoZone. The engine light is on and the code is P2237, The scan shows the exact failing sensor.

 

Unless you've got crazy high mileage, I'd bet the sensor is just the symptom. The car very well may be burning oil, coolant, or too much fuel. All of which can junk up a sensor.

 

Oh yeah, bank 1 goes with cylinder 1, which is the rear of the engine against the firewall.