Where are the O2 sensors located on a 2001 toyota haighlander V6?


Asked by Apr 12, 2013 at 07:00 AM about the 2001 Toyota Highlander

Question type: Maintenance & Repair

I can visually see one of the O2 sensors on the front of the motor (Exhaust manifold) when I open the hood, but where is the othe O2 sensor located on this vehicle?  A picture would be nice.  thanks

24 Answers


So is it the one just after the catalytic converter that appear to have wiring that goes up through the floor under the driver side seat? Someone else said there is 2 up by the motor and that one by the converter? A little confused.lol

21 out of 21 people think this is helpful.

this is the downstream 02 sensor 2001 Highlander V6

11 out of 11 people think this is helpful.

I took down that other one because it was wrong that one id the one on the exhaust manifold.

4 out of 4 people think this is helpful.

ok. Sorry to sound so simple, but there is one on the front (exhaust manifold), and one just before the catalytic converter (Wiring goes up through floor under driver seat), and where is the other located?

5 out of 5 people think this is helpful.

no need to apologize. that's why we are here. I will show you that, but first here is a video it is for Toyota Sienna bit it's the same process http://www.youtube.com/watch?v=Xlt-rc6_cVA..now I will get an image if I can if not at least a description

27 out of 27 people think this is helpful.

Does that image help?

5 out of 5 people think this is helpful.

Not really. On the front of the motor where exhaust manifold connects, there is on sticking out. The exhaust then goes down under the vehicle and back towards the rear of the vehicle where I see the one you were referring to just after the catalytic converter. Still a little confused as to where the other is located?

5 out of 5 people think this is helpful.

There are two "banks" each with a sensor, There is bank 1 sensor one and bank 2 sensor 1...in the image the arrows come from the exploded view and point to where on the car. right by the flange where the manifold is attached to exhaust pipe. You will not be able to see it with the undercarriage pan on

18 out of 18 people think this is helpful.

Put another way, All are heated 02 sensors, there is bank 1, sensor 1 ...bank 1 sensor 2....then... bank 2 sensor 1... and bank 2, sensor 2. But again you will have to take the under engine mud pan off to see them..there are two separate exhaust pipes one for each bank, or side of the V6 ..did you click the image? Important! it will fill half the screen and is very good illustration

28 out of 28 people think this is helpful.

well at least you clicked helpful I see..I don't know if that means you got your question answered...I certainly hope so...what's the trouble anyway? is one or more of them bad? They last a very long time.

2 out of 2 people think this is helpful.

It seems like Duke wants to put eyes on the sensor. He could be planning on replacing it. If the Highlander still has the original upstream sensor(s), it's overdue for changing.

2 out of 2 people think this is helpful.

Yep, he does not mention mileage but I have to agree, they do last a long time but not forever..and I got to thinking I don't know for a fact who clicked helpful, maybe somebody else? that image is so good (I think anyway) it shows everything, and it is a 2001 Highlander, I found it in images for 02 sensors but before I posted it I went to the page it came from to make sure

1 out of 1 people think this is helpful.

Duke9192 if you're suspicious about this sensor, pull it out and test it, inspect to see if it's been eaten away, if it tests okay, put it back-

1 out of 1 people think this is helpful.

It's always a puzzle for us, automakers frequently change their minds about stuff due to legal reasons, or paranoia.....we still don't use the metric system...see my point. Does this sensor have any output? that's why I was asking you to test it. It works in the land of micro-voltages, so if it not an open or zero ohms, we're probably gonna be okay with that one~

1 out of 1 people think this is helpful.

I've seen it to where the critical material was eaten away, leaving just a cavity, still made with the microvoltages though...this was on an Isuzu Impulse, on the main exhaust pipe-

2 out of 2 people think this is helpful.

.http://www.cargurus.com/Cars/Discussion-t26755_ds544223.. that will make it easier to get the link not having it on two lines. I hope.


I found the thread but I know enough about CVT transmission to not own one. It's a good theory but there seems to be issues with them. I also heard that they do not get rebuilt when they wear out. That could be a tale.


Sorry. I work in a prison and had to step away from my desk for a while. I will take that black cover off of the bottom and see if I can see it. I had two codes popping up for the oxygen sensor and I have noticed a decrease in fuel efficiency. So I figured I needed to get them fixed since over the long haul I would be paying for them in gas?lol Thanks


Oh yea...The vehicle has 95k miles on it. Someone was asking about the mileage.

Yep, they get weak around 60k to 80k and at 100k if they are even still working they need to be replaced anyway. Not functioning properly will mess up fuel/air trim

1 out of 1 people think this is helpful.

10-4. Hopefully when I take that black plastic off of the bottom I can get a good visual of the other sensor and get it out. The one on the front is right there where you can get it.

They took down my diagram, it is becoming more and more difficult to find images of public domain, I looked very very carefully and say no watermark or copyright on it, I am aware that CarGurus can not allow copyrighted images, that I understand. but I really checked and I suppose they guy that does it saw something I didn't, oh well, it was such a good one though

see here, if you can call it up on your computer, from the web, all controls have been lifted at that point- any controls should have been used already, like putting the images into .png which makes transfer a little difficult...but cannot escape the camera takin' a snap, which is what I usually do if the source is stubborn about sharing~

here we go, click on the image to enlarge

73 out of 73 people think this is helpful.

Your Answer

Add photo

Looking for a Used Highlander in your area?

CarGurus has 30,383 nationwide Highlander listings starting at $1,990.


Search Toyota Highlander Questions

Toyota Highlander Experts

#1 Tom Demyan
Tom Demyan
Reputation 3,370
#2 Wendy Tucker
Wendy Tucker
Reputation 3,290
#3 Shawntele Lewis
Shawntele Lewis
Reputation 2,270
View All

Related Models For Sale

Used Toyota 4Runner"
378 Great Deals out of 18,519 listings starting at $2,400
Used Toyota RAV4"
1,164 Great Deals out of 48,248 listings starting at $2,495
Used Acura MDX"
490 Great Deals out of 15,311 listings starting at $1,999
Used Nissan Pathfinder"
463 Great Deals out of 24,621 listings starting at $2,800
Used Toyota Sienna"
364 Great Deals out of 25,533 listings starting at $600
Used Toyota Camry"
1,590 Great Deals out of 97,672 listings starting at $895
Used Honda CR-V"
1,605 Great Deals out of 81,341 listings starting at $1,695
Used Ford Explorer"
1,328 Great Deals out of 71,180 listings starting at $985
Used Toyota Sequoia"
169 Great Deals out of 6,664 listings starting at $2,977
Used Toyota Tacoma"
613 Great Deals out of 30,000 listings starting at $2,850
Used Jeep Grand Cherokee"
1,205 Great Deals out of 73,903 listings starting at $1,200

Used Cars For Sale

2016 Toyota Highlander For Sale
20 Great Deals out of 18,760 listings starting at $24,796
2015 Toyota Highlander For Sale
96 Great Deals out of 1,499 listings starting at $22,230
2014 Toyota Highlander For Sale
47 Great Deals out of 901 listings starting at $19,995
2013 Toyota Highlander For Sale
135 Great Deals out of 2,790 listings starting at $15,512