asci01

I'm confused.

How many O2 sensors are there in a 2nd gen GS300?

Is it three or four?

VVT-i

They are 4 of them. Two main sensor before cat. and 2 sub sensors after cat.

enterconne

have you ever changed any of the sub sensors out?? if so, were they easy and how do you do it??

asci01

I don't know what you mean by sub sensors, but I did change the O2 sensor. Piece of cake with the O2 special tool (~$7.00) at pepboys or you can try to use an open wrench of the right size, but to me the tool was worth the $7.00.

enterconne

the O2 sensor is the one after the cat right?

enterconne

by the way, sweet setup with the PC.

asci01

Thanks.

The 2nd gen GS3 has three O2 sensors. One for Bank 1 (cylinders 1,2 and 3) before the cat. One for Bank 2 (cylinders 4,5 & 6) before the cat. The third sensor is after the cat where the exhaust pipes join underneath the car but before they separate again.

enterconne

So if you have a 161 error, Is that the third sensor after the cat??

enterconne

http://us.lexusownersclub.com/forums...e=post&id=3122

check this out!!

asci01

Great find.

Yeap, 161 is Bank 2 Sensor 2 failure.

Check the codes here:

http://www.troublecodes.net/Lexus/

That's the hardest sensor to change because it requires more things to take apart.

Send a quote request to lexus-parts.com. They gave me the best price and offer 1 year warranty. Most other places don't have the OEM and offer no warranty.

enterconne

sensor replaced!!!! thanks for the help.

asci01

You're welcome. If you need to reset the check engine light, you can disconnect the negative cable from the battery for about half hour, although there're other ways to do it.

Happy New Year!

Super400C

Remove the EFI fuse in the underhood fuse box for at least 10 minutes.