I've gotten an OBD error repeatedly for the O2 sensor at Bank 1 Sensor 2 for my 2004 ES330. Just ordered the Denso replacement from Amazon and need to know where on the vehicle this goes.

I'm very handy, but don't have a reference manual for the car. Is it under the hood, or under the car by the exhaust?

Please help. I'm expecting the sensor on Saturday, October 12, 2013. Thanks again!
Marty

 

here you go:

 

I had a zero voltage reading on my Bank 1, Sensor 2 from the OBD computer. This is for a 2004 Lexus ES330. I pulled the original sensor out, and the item number (from the factory unit), is Toyota 89465-33370. The universal Denso replacement number I used is 234-4209.

I reset the OBD, clearing the error code. The new sensor immediately tripped the check engine light, and the code is still Bank 1, Sensor 2. I was getting zero voltage on the old sensor, and with the new Denso, I now get a high voltage error, with 1.250 volts (read from live data stream on my computer). I believe I should be getting near 0.720 volts, which is what the Bank 2, Sensor 2 is delivering.

I'm not sure if I got the wrong replacement part, or a bad replacement part, or another issue that causes the system to read incorrect data from the O2 sensor.

The two photos are of the original O2 sensor, and a third of the universal, which has far more openings than the factory sensor. Any help is appreciated.

 

prob. best to not use a universal replacement. I know Volvos are sensitive to anything but Original sensors, and it doesn't surprise to imagine the lexus is the same

 

Your vehicle may require the california specific sensor.

The sticker under your hood will confirm that.

 

The fact that the part you used does not look the same is a big red flag. I used to have a check engine light because the previous owner installed the wrong oxygen sensor. (Regular vs Cali Spec). Your original sensor looks very clean, which is odd. Has it been replaced before?

 

I returned the universal Denso sensor to Amazon and replaced with the Denso direct fit part. Took about 9 minutes plus clean up to swap the sensor. The OBD monitor displayed a nice 0.72-0.85v from live data. Been a week and MIL light is still off!

Cost me $56 and a few hours dicking with, and returning, the wrong part. Lesson learned.

Enjoy your day!
Marty

 

Bank 1 = Left
Bank 2 = Right
Sensor 1 = Upstream
Sensor 2 = Downstream


ES300 200 Lexus Bosch Part Numbers for Oxygen Sensors

 

Hey Marty,

I hope you don't mind me jumping in here... DId you get your P0136 code resolved?
It looks like I have a similar problem in that the Denso O2 sensor I've received doesn't look like the toyota sensor on the car!
The new sensor has lots of holes and the original only seems to have 1... The Denso part number is:

234-4064

Which is OE according to Amazon and the Denso website... so hopefully the cosmetic difference isn't a problem!?

Thanks!

Rich

 

Good morning, I'm having a similar issue. I need to replace the bank one sensor 2 02 sensor. I was curious, what specific sensor did you buy, like what's its model number? It was recommended to me to get the denso 234 4261 But I want to make sure that is the right part before buying. Your story is definitely evidence of why it pays off to check twice. Any advice you can give would be greatly appreciated.

 

Hello,

What year do you have?

It appears that Denso 234-4261 is for Bank 2 on the Front of the engine, closer to the radiator. In those engines it's a little backwards, with Bank 1 being closer to the Firewall, so you likely need a Denso 234-4064 instead, here is a good place to get one. Not that big of a difference, just a different connector housing that can easily be replaced if needed, here is a thread on how to do it.

Hope this helps and best of luck!

 

I have an 04. I agree, rockauto was the best place to go, it's actually where I source all my parts. I believe I found the location of b1s2 Yes too on my car. I was having issues trying to figure out which of the two sensors on RockAuto I should go with. From what I can tell both of the ones I was looking at are also the two that you recommended. The only difference between them is that one is for the front and one is for the rear. I'm assuming I need a front since this is going to be going in front. I've definitely over thought this because some of my other research shows that front and rear sensors are identical hardware despite having different IDs.

I think I'm going to go with the front variation. Funny thing is, the situation fixed itself, just as fast as it showed up today it went away. My theory is something in the air pressure is causing the reaction, I live in New England. Something also worth noting is that a lot of people suggested may just be the air filter

 

Sorry, not quite sure if I was clear enough..

As written earlier, that engine is backwards, with Bank 1 being closer to the Windshield, and Bank 2 is closer to the Radiator. In your case, it is Bank 1 sensor that you need, it is on the Back of the engine, so you need a Rear sensor linked above.

Again, the difference is just in connector used, and you can make the other sensor work, but it's easier to get a correct one.

Hope this helps and best of luck!

 

Hi Maty,
Do you recall the code? I have a P0171 but not sure if the sensor is bad specifically. Thanks.

 

Here is a recent thread on the subject with a very similar issue to yours.

Hope this helps and best of luck!