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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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.
OSA61217
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Product Reviews
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02 sensor
Joe
October 16, 2018
Very happy with customer service . Was here in three or four days . I will definitely be ordering more parts from you guys .
Worked as expected
William
June 20, 2024
Worked as expected in a 2500HD 2004 Chevy Gas
Part match
Joshua
October 14, 2024
Part matched but didn't resolve my check engine code
Customer Q&A
This states it fits the 4.3 and 6.0. Does this fit the 5.3 and are they the same for bank 1 and bank 2?December 11, 2015
Samuel S
10
Hello and thank you for your inquiry. This will fit different applications for different vehicle. It does not appear to be bank sensitive, but can fit downstream per the application. Thank you and have a great day!
December 16, 2015
Derek C
10
My system has an upstream and downstream sensor so I am unable to answer your question.
August 11, 2017
A L
10
Bank 1 and 2 are different sensors. Also different capacity engines take different sensors.
January 13, 2019
T H
10
yes
February 23, 2019
Derrick M
10
yes
June 21, 2019
Betty P
10
The work on my 5.3. Both banks have the same sensor requirements.
May 3, 2020
Eric D
10
Put on a 2012 GMC ACADIA SLT 3.6L . Came pre greased with cap and ready to go. Fit was perfect and solved my issue.
November 10, 2020
Jason H
10
No
March 25, 2021
Orwson- C
10
No
March 31, 2021
P A
I have a 2003 chevy silverado 2500 hd with the 6.0, will this fit my bank 2,downstream 2 on my truck?July 31, 2021
John D
10
Im but I dont know. The connection on the pins are not interchangeable but 1A Auto is very good at getting you the correct part as long as you are correct on the correct bank and location.
July 31, 2021
Peter W
10
1aautos add says it will
August 1, 2021
William R H
Will this sensor go for bank 2 sensor 2?October 28, 2022
Cochise S
10
Can you provide us with the year, make, model and engine size so we can confirm fit?
October 28, 2022
T I
Would this 02 sensors go for 2007 Pontiac g6 gtp downstream bank 2 sensor 2 and if so is there a way you can tell me where is bank 2 sensor 2 located on the car check engine light and thats what it said?October 31, 2022
Cochise S
10
Yes, this part will fit the sensor 2 bank 2 location for your model. We do not have any diagram showing where this is installed.
November 1, 2022
T I
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