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Thought this may help others as others have helped me out on this forum.
Lexus 2007 -2012 Air/Fuel (A/F) and Oxygen (O2) Sensor Guide
This bulletin contains information that identifies engine bank 1 and engine bank 2 on
the following engines: 2GR–FE, 2GR–FSE, 4GR–FSE, 2JZ–GE, 1MZ–FE, 3MZ–FE,
1UR–FSE, 3UR–FE, 1UZ–FE, 2UZ–FE, and 3UZ–FE.
TERMINOLOGY:
�� Bank 1 (B1) refers to the bank that includes cylinder No. 1.
�� Bank 2 (B2) refers to the bank opposite bank 1.
�� Sensor 1 (S1) refers to the sensor that is located before the catalytic converters.
�� Sensor 2 (S2) refers to the sensor that is located after the catalytic converters.
Terminology Continued ---
There are a total of 4 oxygen TYPE sensors. TECHNICALLY, they are:
(2) Air/Fuel (A/F) sensors located on the exhaust manifold, 1 per bank. Also called “Upstream”.
(2) Oxygen (O2) sensors located AFTER the engine mounted catalytic converters, 1 per bank. Also called “Downstream”.
Bank 1 (B1) is located nearest the firewall. Also called “Right”.
Bank 2 (B2) is front of engine, also called “Left”.
Ex. If you need to replace the Bank 2, Sensor 2, you would look for an O2 sensor, B2S2, Downstream, Left.
If you need to replace Bank 1, Sensor 1, you would look for an A/F sensor, Upstream, Right. B1S1, OR (see note below) look for an O2 sensor, Upstream, Right.
Note: When looking for replacement parts, be aware that the term “oxygen sensor” or “02 sensor” is a broad term used by some part companies to also describe the “air fuel sensor”, so double check the part. “Upstream” for the ES-350 means an Air Fuel A/F sensor, though some companies will call it an O2 sensor.
Thanks for all the pics above. I just bought my 08 ES 350 and was trying to figure out where B2S2 was located and how to replace it. Your pics were spot on to what I have found when looking at my engine.
Question, and I am taking a gamble you will get this since the thread is a little aged. :-) Did you have to remove the carpet, console, and seat to replace? From where I'm lying, I can unscrew the sensor and pop the plug at the other end, screw and pop back in, and I am finished. Am I simplifying this too much? All the videos and other threads I watched/read seemed so labor intensive and lots of disassembling. Although not a trained mechanic, owning used cars my entire life, I know my way around an engine. My current plan is to do the above (plug and play) and if that doesn't work, continue with the wiring harness end of the plug in that appears to lie under/near the carpet/console area.
Thanks again for the pics! Very helpful to this chic!
Thanks for all the pics above. I just bought my 08 ES 350 and was trying to figure out where B2S2 was located and how to replace it. Your pics were spot on to what I have found when looking at my engine.
Question, and I am taking a gamble you will get this since the thread is a little aged. :-) Did you have to remove the carpet, console, and seat to replace? From where I'm lying, I can unscrew the sensor and pop the plug at the other end, screw and pop back in, and I am finished. Am I simplifying this too much? All the videos and other threads I watched/read seemed so labor intensive and lots of disassembling. Although not a trained mechanic, owning used cars my entire life, I know my way around an engine. My current plan is to do the above (plug and play) and if that doesn't work, continue with the wiring harness end of the plug in that appears to lie under/near the carpet/console area.
Thanks again for the pics! Very helpful to this chic!
SteffieK, I apologize for not replying soon, as I never received a notice that you had posted a question. I just happened to look at this again today (almost a year later) to find your question, which by now, I am sure you have answered.
How difficult it is to remove depends on which sensor is bad. That said, there should be NO reason to remove anything in the interior of the car, as the sensors are all accessible from the engine compartment or under the car. Looking back at what I posted, I should have stated that the sensor by the firewall was the most difficult BECAUSE you have to either go up under the car between the firewall and the engine, or take the top cross bar off to get access it from the top of the engine. Either way, it is a p.i.t.a. I hope it was an easy to access sensor fix for you.
Also, anyone else reading please note that since this was posted a few years ago, another member mentioned in a different post that DENSO changed the part number of one of the sensors, so be sure to know the exact location and name of the sensor you need.
Thought this may help others as others have helped me out on this forum.
Lexus 2007 -2012 Air/Fuel (A/F) and Oxygen (O2) Sensor Guide
This bulletin contains information that identifies engine bank 1 and engine bank 2 on
the following engines: 2GR–FE, 2GR–FSE, 4GR–FSE, 2JZ–GE, 1MZ–FE, 3MZ–FE,
1UR–FSE, 3UR–FE, 1UZ–FE, 2UZ–FE, and 3UZ–FE.
TERMINOLOGY:
�� Bank 1 (B1) refers to the bank that includes cylinder No. 1.
�� Bank 2 (B2) refers to the bank opposite bank 1.
�� Sensor 1 (S1) refers to the sensor that is located before the catalytic converters.
�� Sensor 2 (S2) refers to the sensor that is located after the catalytic converters.
Terminology Continued ---
There are a total of 4 oxygen TYPE sensors. TECHNICALLY, they are:
(2) Air/Fuel (A/F) sensors located on the exhaust manifold, 1 per bank. Also called “Upstream”.
(2) Oxygen (O2) sensors located AFTER the engine mounted catalytic converters, 1 per bank. Also called “Downstream”.
Bank 1 (B1) is located nearest the firewall. Also called “Right”.
Bank 2 (B2) is front of engine, also called “Left”.
Ex. If you need to replace the Bank 2, Sensor 2, you would look for an O2 sensor, B2S2, Downstream, Left.
If you need to replace Bank 1, Sensor 1, you would look for an A/F sensor, Upstream, Right. B1S1, OR (see note below) look for an O2 sensor, Upstream, Right.
Note: When looking for replacement parts, be aware that the term “oxygen sensor” or “02 sensor” is a broad term used by some part companies to also describe the “air fuel sensor”, so double check the part. “Upstream” for the ES-350 means an Air Fuel A/F sensor, though some companies will call it an O2 sensor.
I have a 2007 Lexus GS 350 my service enigine light is on and I had multiple error codes I changed my mass airflow sensor now I have 2 codes 1 is for catalytic bank 1 and the other is for bank 2, is there any other way I can fix this problem with out shelling out 2500 to the dealer?
07-18-15, 07:48 PM
ES-350 Air Fuel and Oxygen Sensor Info
