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.
Quality Tested - built to a strict level of product standards.
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.
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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
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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.
OSA61332
In Stock
Product Reviews
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4.43/ 5.014
14 reviews
5 Stars
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Easy
M
August 30, 2017
I receive the part one day. The next day it took 15 minutes to pull the old one off and install the new one. Exact fit, fix the problem, So easy!!!
Great Value on Acura O2 Sensor
Jerome
March 30, 2018
the price was right but with no brand name i was a bit worried. Product showed up in a very generic box with bubble wrap. threads were pre lubed with anti seize. there was no need for me to worry. Installed and works great. Codes cleared and have not come back on.
Thanks 1A,
jerry
Awesome customer service
lee
March 26, 2019
Oxygen sensor was the perfect fit. I was a little confused by the part listing and just wanted to make sure that it was the right part. I called and a man(I forgot his name)was super helpful and made sure the part was what I wanted. Part came on time and it works perfect.
O2 sensor
I
December 19, 2019
I got the product fast, I just got the wrong one. I happen to get the one for the bottom of the engine
O2 sensor
O
February 18, 2020
Fast shipping and correct part to clear code.
Wrong part
Donald
April 9, 2020
Trying for abut two weeks for 1A Auto to determine the right P/N. It seems that 1A Auto sent me a Down Stream O2 sensor instead of an Up Stream O2 sensor.
The P/N I purchased was given me by an 1A Auto person on the phone, after I couldn't figure out the correct P/N on the 1A Auto on line catalog. Hoping for a resolution in the near future, so I can pass my smog test.
Not your finest hour.
On the positive side, your How To videos are quite good.
Went bad after 7 months
M
September 30, 2020
Ordered the part Aug 24th so i got it shortly after, put it in was working great up until 7months in. Thought maybe it was the Catalytic converter on my car that went bad or something throwing my o2 sensor off but nope lol. Just a bad o2 sensor, was disappointed because these are supposed to last at least 50k-60k long. Just barely passed a year of having it in and i don’t drive more than the average person if anything i drove less due to Covid-19. Was cheap though so can’t be too mad.
06 Honda Pilot
Toua
January 24, 2021
Replaced my old one because of check engine light issues, and right away it fixed the problem!
Duane
June 30, 2021
This part came quickly and was just as described.
Willie
August 20, 2021
No more check engine light, drives so much smoother and efficiently. Very strong acceleration! Love the high quality products from you all.
Edward
September 27, 2021
exact fit in out 10 mins if it last you can't go wrong will definitely buy more products
07 honda ridgeline
Shannon
December 10, 2021
Worked great first start engine light was off been getting better gas milage since
Aaron
April 19, 2023
Works well. Looks like a quality build.
Great product.
Thomas
May 13, 2023
Perfect fit. Solved my problem. Highly recommend!
Customer Q&A
I have ordered this and waiting for it to get here, is this an OE part?April 10, 2020
C D
10
Hey Dawn,
This part is meant to replace the original equipment.
April 11, 2020
Corey M
Does the connector have a slot to attach to the bracket?September 19, 2021
John D
10
yes
September 27, 2021
Edward B
I need both o2 sensors bank 1 bank 2 up stream for a 2007 Acura TL s type v-6 3.5 no need both parts ?November 16, 2021
John D
10
Yes this will fit both upstream banks for that vehicle!
November 16, 2021
T I
I have acura rl 2005. Is this upstream o2 sensor fit for both banks?January 11, 2022
John D
10
I cant remember, I bought it for the down stream. But I think it will work for both but Im not sure
January 11, 2022
Daran P
10
Yes this will work for both banks!
January 11, 2022
T I
10
I believe it does fit both banks. Fixed my problem.
January 11, 2022
Mike S
10
I cant remember, I bought it for the down stream. But I think it will work for both but Im not sure
January 11, 2022
Daran P
I need the sensor installed quickly-I also need a Smog in sacramento area-suggestions?can you give me referral?March 12, 2022
John D
I need the sensor installed quickly-I also need a Smog in sacramento area-suggestions?can you give me referral?March 12, 2022
Gloria F
I have an 2004 acura tl will this sensor work for both bank 1 sensor 1 and bank 2 sensor1?July 19, 2023
Oscar R
10
This part is listed to fit the 2004 Acura TL V6 3.2L Upstream.
July 29, 2023
Kemal S
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