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.
OSA61198
In Stock
Product Reviews
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4.65/ 5.020
20 reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
16
3
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1
Packed and ship.
F
February 9, 2018
The item I ordered was well packed and shipped in a timely manner. It also arrived sooner then expected.
Just what I needed
Luis
April 24, 2018
Exactly what the engine light needed, payed 1/5 the cost. Ill be checking here for my replacement parts from now on
good fit...seems to work fine
Mark
February 27, 2019
wires/casing not as robust as Honda's....need to add filler to firmly stay in routing clip on frame.
Great Product
E
April 3, 2019
I purchased my o2 sensor and got it within a few days and it fixed my issues.
Perfect fit, high quality, good price
chris
June 18, 2019
1A auto is my go to ever since I had a problem with a wrong part and they went above and beyond to correct it. Ordered this O2 sensor and it arrived quickly and was better priced than everything but the "eBay" knock offs
O2 sensor
Zeeshan
August 24, 2019
O2 sensor for my Element fit perfectly. CEL is off now. Great price and fast shipping. Thanks 1A Auto!!!!
Wrong Sensor Description
Charles
February 6, 2020
Purchased this sensor because the listing said it was for upstream. Ended up being the downstream sensor instead. I still am giving this 5 stars because the shipping was fast, the quality was good, and 1AAuto customer service has always been excellent. Thanks again!
Oxygen sensor
Ramiro
July 29, 2020
The oxygen sensor plugged right in. Worked perfectly.
o2 sensor
Skye
August 20, 2020
worked well plugged in no problems
Excellent Service
I
November 3, 2020
This company takes care of their Customers
Responds right away
Listen to your concerns
Sensor
Robert
April 22, 2021
Worked great. No more check engine light on.
Works
Felipe
May 11, 2021
Works. Replaced this one and another I bought from Amazon. Removed my check engine. Although after replacing other sensors and problems began showing up. Not sure if it has to do with using this sensor.
Works great, even after 8 months.
Tyler
June 13, 2021
Actually works. unlike other 1aauto parts Ive bought. I installed this a few months ago and it worked immediately (with an OBD fault code reset and new #4 fuse). I do see truth to some reviews that say the thickness of the plastic harness is not quite to factory and creates a weird fit... but it does fit. And at a much lower price than the factory piece. This is one of the very few 1aauto parts I actually recommend. Given the outrageous price to replace this part, especially if you're replacing as a result of a stolen catalytic converter, you can save some money by getting this.
My car it's working better
Neftaly
September 10, 2021
Perfect
Great buy
Mark
September 14, 2021
Installed with no issue, have used it now for 6 months and it is working great. Had to do a reset on the engine start to get it to register on the computer, but once that was done all was well.
Great
Tammy
February 27, 2023
Still working
Good replacement part.
Ruzivo
May 21, 2023
Fit and functions as it ought to. So far works well.
Works great
Jesse
June 12, 2023
So far works great
William
June 28, 2024
Junk just cheap junk
Great fit
max
October 2, 2024
Worked just as expected
Customer Q&A
Is this used for upstream and down stream on a 2000 civic 1.6?March 27, 2016
Roland S
10
1999-2000 Honda Civic EX Upstream O2 Oxygen Sensor for 1.6L
March 28, 2016
Brian F
10
I wasnt able to use it on my 2000 Honda Civic LX because of the female connector. Make sure your car has the right receiving end. This part has a female connector so did my car, I needed a male connector. Other than that, it can be used for up stream or down stream. Keep in my that one needs a longer cable than the other.
March 29, 2016
Erick M
10
I think it depends. I have an 05 civic hybrid and the up and down sensors are different ends. This senor only works to replace the downstream sensor. The upstream has a different end.
July 30, 2023
Joshua C
Are there two sensors included or can they be used interchangeably for upstream and downstream?January 2, 2020
Stef S
10
no there 2 different ones
January 2, 2020
S T
10
Thank you for your inquiry. This purchase would include 1 O2 sensor. The position of this O2 sensor would depend on your year, make and model vehicle. Please let us know if you have any further questions.
January 2, 2020
A C
10
as far as I know there are two sensors and they arent interchangeable. The one I purchased was a downstream sensor and worked fine.
January 3, 2020
Mark W
Is this compatible with honda civic es5 2003 car?February 6, 2024
Anoja K
10
Please provide your full vehicle information or VIN number to confirm product availability and fitment.
February 6, 2024
Nick R
Customer service
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