TRQ oxygen sensors are manufactured to precise specifications using premium raw materials to optimize your vehicle’s emission system. Each sensor is isostatically-pressed for improved strength and durability, and plasma-sprayed to improve sensitivity and prolong the service life of the sensors. Oxygen sensors wear out over time and should be replaced every 60,000 miles to prevent poor engine performance. TRQ recommends replacing the oxygen sensors in sets to optimize fuel economy and reduce overall emissions. All products are fit and road-tested in our Massachusetts R&D facility to ensure we deliver on our promise of Trusted Reliable Quality.
Product Features
Application Specific Design: No modifications and pre-calibrated
Isotatic-pressed and plasma-sprayed for extended service life
Double-Layered 310S Stainless Steel: Additional protection from moisture and debris
Restored Engine Performance: Improved fuel economy and lower emissions
What is Upstream vs. Downstream?
Upstream location is between the catalytic converter and the engine
Downstream location is between the catalytic converter and the tailpipe
Install Tip: You may be required to reset the vehicle computer after installation of this part.
Item Condition:New
Attention California Customers:
WARNING: This product can expose you to chemicals including Lead and Lead Compounds, which are known to the State of California to cause cancer, and birth defects or other reproductive harm. For more information, go to www.P65Warnings.ca.gov.
Lifetime Warranty
This item is backed by our limited lifetime warranty. In the event that this item should fail due to manufacturing defects during intended use, we will replace the part free of charge. This warranty covers the cost of the part only.
Returns: Parts with electrical components cannot be returned once installed.
FREE Shipping is standard on Orders shipped to the lower 48 States (Contiguous United States). Standard shipping charges apply to Hawaii, Alaska and US Territories. Shipping is not available to Canada.
Expedited is available on checkout to the United States, excluding Alaska, Hawaii and US Territories as well as P.O. Boxes and APO/FPO/DPO addresses. Final shipping costs are available at checkout.
O2 Sensors is it Upstream or Downstream
Created on:
Tools used
No Tools Needed
1. Identifying your Oxygen Sensors
Upstream oxygen sensors are located in between the engine and the catalytic converter
Downstream oxygen sensors are located in the catalytic converter or farther away from the engine than the catalytic converter
Locate your vehicle's firing order diagram
The bank that contains cylinder one is bank one
The bank that does not contain cylinder one is bank two, even if it does not contain cylinder two
Hi, I'm Mike from 1A Auto. We've been selling auto parts for over 30 years. We're dedicated to delivering quality auto parts, expert customer service, fast and free shipping, all backed by our 100% satisfaction guarantee. Visit us at 1AAuto.com, your trusted source for quality auto parts.
In this video I have a couple of oxygen sensors with me. While there are some aesthetic differences here, the wire lengths are a little different, the actual body and tip of the sensor are a little different, the threads and gasket are the same, and on the other end the connections are actually the same. I can plug these into either position on our vehicle. But if I had to ask you which one's upstream and which one's downstream, you probably can't tell just from looking at them. That's true of most oxygen sensors. The way you determine whether or not an O2 sensor is upstream or downstream is all done visually.
Your oxygen sensor position can be determined relative to your catalytic convertor. As the name suggests, upstream sensors will be located upstream or ahead of, in front of, above, closer to the engine than your catalytic convertors. This means that they see the exhaust gasses first. They then go through the catalytic convertor and to the downstream oxygen sensor, which will either be located in the catalytic convertor like our vehicle here, or after the catalytic convertor to monitor the gasses coming out of the cat and make sure that it's being efficient relative to the readings of the upstream O2 sensor.
The other determination you need to make is bank one versus bank two. Determining which bank is which can be done by looking at a picture of your vehicle's firing order. Whichever bank contains cylinder one is going to be bank one, and the other one, regardless of whether or not cylinder two is in it, is going to be bank two by default. These banks are true of V engines like V8s, V6s, and flat engines like Porsches and Subarus that have individual banks.
On inline four-cylinder engines, as long as they have one exhaust manifold like a Jeep four-liter or a four-cylinder Honda engine, you'll only have one bank with an upstream and downstream O2 sensor. There will be no bank two on the engine.
On our vehicle here, this is the passenger side, which we've already determined from the firing order is bank one. We have our upstream sensor here closest to the engine ahead of the cat. Then we have our downstream or sensor two here inside of the catalytic convertor. This could also be located somewhere after the cat. Here I have my two sensors for the vehicle. While they are aesthetically different, we can now tell this is my upstream sensor because it looks just like the upstream sensor I have up there. This is my downstream sensor. Now that we know which one's which, we can order the right part, correct the problem, and fix you up right.
Thanks for watching. Visit us at 1AAuto.com for quality auto parts, fast and free shipping, and the best customer service in the industry.
OSA61635
In Stock
Product Reviews
Loading reviews
4.57/ 5.021
21 reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
16
3
1
0
1
Gas Milage Salvaged
Edward
May 22, 2018
I had 2 failing O2 sensors in my 2000 ford explorer. I was getting lean fuel readings and poor gas mileage. I went a head and purchased these. My fuel trim readings have gone back to factory spec and my gas mileage has been greatly improved. Great purchase.
O2 sensors
Michael
October 24, 2018
Fit and worked perfect.Only been installed a few days but are working fine.
Mike
October 29, 2018
Perfect fit. Easy to install. My engine light finally went out.
O2-Oxygen Sensor
X
October 31, 2018
Pleased with the service and shipping time. Will contact with my next purchase
Fast and accurate
Brian
November 28, 2018
I ordered these O2 sensors for my 08 Ford Ranger. They were shipped to me quickly and they fit perfectly. So far they have performed flawlessly.
Arkent
December 2, 2018
Great quality products I will recommend to my friends and family.thank you for quick shipment.
service and is great
Timothy
April 5, 2019
Write parts never hade problem will order aginen
Right Parts Right Price
J
September 30, 2019
Needed to replace my catalytic converter on my van, of course it was a custom unit and had to be ordered from a muffler manufacturer but was able to get it and then went the extra step and got both up and down stream O2 sensors to make the job complete. Everything went on fine and no problems, could not find these O2 sensors less expensive anywhere else!!!
Fit perfectly
Wanda
March 7, 2020
My son put the sensors on my truck and they fit perfectly. My truck runs much better. I love the price I paid. If I would had gone to a store, it would have cost me twice as much.
J
September 22, 2020
You all are the best and I appreciated your support!Very nice and professional group.thanks Ms Moreno
O2 Sensor
F
November 5, 2020
Received and installed and works fine. I am satisficed
Good value for the price
Gary
May 25, 2021
Bought these to save on the cost of OEM, they seem to be good quality, and fit properly(albeit they are a hair longer than the originals). The wire wrap is better than my factory originals, goes all the way from connector down to the sensor, old ones barely covered any. Made in China printed right on the box so if this bothers you be aware, I expected it due to the low cost. So far so good, have jad them installed on my new converters for about two weeks with no issues yet.
Perfect product!
David
December 9, 2021
Was able to get my 4.0l ranger running like new with these new 02 sensors. Significantly improved my performance, power & mpg on my truck. Least expensive option for a pair of two sensors. Others charged same price for one.
Frank
May 7, 2022
Grate part exact fitment
David
August 17, 2022
Very good products too by
Not work.
Liam
September 30, 2022
They don't work. Still getting an o2 sensor code, and still didn'temissions.
corey
March 4, 2023
Great fit
Corey
March 4, 2023
Great fit
1/2 good
Stephen
April 15, 2023
1 sensor was bad according to
scanner. inquired about return
defected sensor, had to return
the complete order. I bought a single sensor locally to finish
the job.1/
Great product
Bernabe
July 1, 2023
The items that I received were all the same, call customer service and they assured me that they will work, when I remove the old ones if fact, they were the same once I installed them the truck is running a lot better.
O2 sensor
Richard
October 31, 2023
Auto Zone price was 59$ for one. 1Aauto had the pair which Fit prefect and had a little longer connecting wire which made it easier to connect! For the price of one locally.
Customer Q&A
who makes the oxygen sensor that yall sell for the ford f150 2006?July 30, 2018
Blake M
10
We have a few different aftermarket companies build these parts specifically for us, as our 1A Auto house brand. They are manufactured to the same OEM specifications as the original part that came with your vehicle. If you have any further questions, please don't hesitate to ask.
July 30, 2018
Peter L
10
DIY solutions brand parts are manufactured by various aftermarket companies specifically for us and built to your vehicle's exact OEM specifications.
April 14, 2021
Ricale A
I need 4 oxygen sensors for 2000 Mercury Mountaineer V8 do i just enter the number quality and thats it or do i just enter 1 and it comes with all 4 sensors?May 27, 2019
Melvin M
10
If you need to change all 4 then order the 4.My 2005 Ford F-150 needed 2 oxygen sensors and thats what I ordered.You can also call them direct and speak to a person that can help with your order.Hope my answer helps
May 27, 2019
A C
10
It is a pair, just put in 2 for 2 pairs
May 28, 2019
D A
10
If I remember correctly, the sensors come in pairs. You will need to order 2.
May 28, 2019
S A
10
This listing is just for 2 Upstream sensors for your vehicle if it has a V8 5.0L engine. You will also need 2 for the Downstream. Please take a look at part WKEOS00010 for the Downstream. You will need to order 2 of these.
May 28, 2019
Christa R
I need both sensors next to engine ( I guess forward sensors ) will these fit my 2007 f150 5.4 ford ?September 22, 2021
John N
10
Yes, this part will fit your vehicle.
September 22, 2021
Emma F
10
Yes, that is what you will need. When I replaced them on my 2001 Ford Expedition, 5.4l is was not too difficult as long as I used penetrating spray and let it sit overnight to help loosen the old 02 sensors. I then went ahead and replaced the two rear 02 sensors also. Same methods.
September 22, 2021
Thomas F
Need up and down stream sensors for 2011 4.6 engine E150?April 8, 2022
Calvin W
10
This is not the correct part for your vehicle, but we do carry the one you need. The correct part number is: 1AEEK01266
April 9, 2022
Cristina P
What is the part number for the down stream sensors for a 2007 Ford F-150?May 21, 2022
I ordered two upstream 02 sensors for my 4.0 ranger, they are sending 02 sensors for 3.0 ranger. Are they the same ?January 6, 2023
Doyle K
10
These will fit the following Ranger variants:
2001-2008 Ford Ranger V6 3.0L Upstream
2001-2011 Ford Ranger L4 2.3L Upstream
2001-2011 Ford Ranger V6 4.0L Upstream
January 6, 2023
T I
Do the 02 sensors for 2008 F150 work with 4.6 L and 5.4L?January 20, 2023
Thomas A
10
These sensors will work for the following vehicles:
2005-2008 Ford F150 4.6L Upstream
2005-2008 Ford F150 5.4L Downstream
2005-2008 Ford F150 5.4L Upstream
2005-2008 Ford F150 4.6L Downstream
January 20, 2023
T I
Customer service
877-844-3393
Monday - Friday 8:00am - 9:30pm ET Saturday - Sunday 8:00am - 4:30pm ET
Ford is a registered trademark of Ford Motor Company. 1A Auto is not affiliated with or sponsored by Ford or Ford Motor Company.See all trademarks.
Enter Vehicle Year Make Model
Specify your vehicle's year, make and model to guarantee fit.
Year
Make
Model
Options
Drivetrain
This part doesn’t fit a . Select from parts that fit.