chenxingha

Attached is a PDF file on the components of the emission system.

My question is about the identification name of the Oxygen Sensor (as vs. A/F sensor). On Page EC3, the oxygen sensor is identified as Bank 1 Sensor 2, but on Page EC11 the same oxygen sensor is identified as Bank 1 Sensor 1. Which identification is correct?

Also, what is the size of the two nuts that fix the oxygen sensor to the mounting bolts on the pipe? What does the mark 22(100, 14) (next to the nuts on Page EC11) mean?

Thank you for your help.

razali2k5

Identification on page EC3 is correct for the post-cat sensor.

You might want to check out https://www.clublexus.com/forums/rx-...sor-2-diy.html

The part number of the 12mm nuts is 90179-08059

code58

Raz is correct, page EC3 is the correct identification. Page EC11 is in error, not the 1st one I've ever seen in a genuine T/L shop manual. Whoever does their shop manuals doesn't seem to check for accuracy.

artbuc

Many errors, especially electrical. The troubleshooting instructions for the IACV are entirely wrong - written for the IACV in my Avalon. To their credit, Lexus gave me a complete refund for the IACV I bought unnecessarily.

chenxingha

Thanks for the clarification about the oxygen sensor identification.

Regarding the size of the nuts: it took me many tries and I eventually found out that the nuts are of M8 x 1.25 on both of the 2000 RX300 vehicles in my household.

In the link to Lexmex's DIY for replacing the oxygen sensor, it shows one-nut-and-one- bolt mounting, while on my vehicles the mounting uses two M8 x 1.25 nuts with a protective shield (the protector) exactly as shown in the attached shop manual. In other words, the mounting on my two RX300 is somehow different from those shown in Lexmex's pictures. No idea why.

razali2k5

I replaced this sensor recently and I can confirm that my setup is like yours. Lexmex's pictures made me weary at first.

code58

I believe the answer might be that some of the things on LM's RX were a little "modified" (by necessity) when he lived in Mexico. I'm sure he will be able to clarify that for you.

Lexmex

On my RX300, the bolts are OEM, so I am not sure why there would be a difference there.