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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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.
OSA61312
In Stock
Product Reviews
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3.09/ 5.023
23 reviews
5 Stars
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Great!
M
July 4, 2017
It arrived before it was suppose too and is working great in my car!
Great product
J
November 10, 2017
Good shipping. Could be better specs for compatible. Narrow or wideband Heated? Instructions? It's easy install.
T
February 19, 2018
The cost of this part was a major factor since the original part was well over $300. Even though this part was way less expensive, it was recognized by the car which got rid of the check engine light. It even had anti seize compound on the threads. Very satisfied!
Fast reliable and fair
R
April 17, 2018
I ordered this piece after the auto shop told me I needed one and my car works perfectly. Thanks
Amazing fitment
B
October 15, 2018
Perfect length. Equivalent to oem! Worked perfect! Fit great!
Fixed the engine light
Charity
October 27, 2018
I know many people worry about a an off brand part not working for the engine light but this did and it was literally $100 cheaper. This part was a true blessing from God but I couldn't afford the other part. Did the job well! I recommend to everyone!
It does not wrk
A
February 22, 2019
I installed the product and it solved the problem for the first 24 hours and then the check engine light came back on.
Bad sensor
Manuel
April 13, 2019
I bought this oxygen sensor for my 04 Honda crv but the sensor didn't work, my mechanic tested it and he told me the sensor signal was dead, so we replaced it for a new Denzo 0xygen sensor and after that everything work great no more check engine light on..
betty
June 20, 2019
It fit our vehicle perfectly so no complaints, very happy!
O2 sensor
HUGO
August 12, 2019
Great sensor,great price,I installed works just fine the ECU didn't have any trouble identifying it
Reliable
jevola
October 7, 2019
Good quality product good service
T
April 14, 2020
It didnt work
04 Honda Civic O2 sensor not OEM specs
Chris
April 26, 2020
After installing the O2 sensor from 1A Auto I cleared the codes and within one day the check engine light came back on. The specs on this O2 sensor does not meet the oem specs and is not recommended for a seventh gen Honda Civic.
03 Honda CRV O2 Sensor
O
September 2, 2020
Buy OEM like Denso, even though it may be more expensive. This sensor did not erase a code, it brought another one. Save the time and just get OEM!
Good Value
Michael
November 21, 2020
Worked on my car although the connecting chord was shorter than the original so I couldn't secure it on the bracket the original one was supported on.
Great
Michael
March 6, 2021
Fit perfect. Did the job. No check engine. Wire length was perfect.
Better than the broken one.
Matthew
October 7, 2021
Bought it because 1A auto had an awesome video explaining and showing me which o2 sensor was responsible for AFR. Noticed it was very inexpensive. Like half the cost of other companies mid priced option, in line with the least cost option.
I usually buy the mid cost option and regret that 1A did not stock one. This inexpensive unit addresses some of the misfires but not all of them. Only a partial fix for the problems I was having.
P
February 19, 2022
it is too soon to rate it,
i just installed it , give me few months
Don't cheap out on the sensor, get Denso
Ruben
September 27, 2022
Engine light came back on after installation. Reason why I bought it was because it was cheaper than the denso brand. Also, bought downstream sensor to rule out the same code if it popped out again. Will have to replace upstream sensor again and pray I won't have to buy downstream.
05 Honda Civic
Nicolas
October 3, 2022
1A auto had a great video explaining how to install but once I installed and drive for 5 minutes the check engine came back on. Fitted and looked fine but didnt net the requirements.
Not good for honda crv 2004
Bryndan
December 19, 2022
The TRQ 02 Senor did not work.
After I installed a densor o2 senor the code went way .
Oxygen sensor caused a manufacturer specific trouble code, had to put old sensor back on vehicle.
AMARJIT
July 19, 2023
First O2 sensor was faulty and replaced was no good too.Called again but no body responded up to now.
Customer Q&A
Does this fit the ex sedan?September 22, 2017
H E
10
no
March 3, 2022
Todd C
Will this fit my 2003 acura rsx base model with automatic transmission?November 2, 2017
Den G
10
What is the engine size of your RSX Base?
November 2, 2017
Alex P
hi, Dose it fit my 02 Honda CRV Touring model ?April 10, 2020
Rama P
10
Yes, according to the information you provided, this part will fit your vehicle as long as you have a L4 2.4L. Please let us know if you have any other questions!
April 10, 2020
Emma F
Will this fit into my 04 Honda Civic ex 1.7L?July 18, 2020
Daniel H
10
Currently, we do not carry this part for your vehicle. We're always updating our inventory so please check back soon! If you have any other questions, let us know.
July 19, 2020
Curtis L
Is this with California Regulations?May 17, 2021
Sultan A
10
This part can be used in vehicles in CA. We cannot ship our catalytic converters to your state.
May 18, 2021
Christa R
Customer service
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