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Part Details
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
What is Upstream vs. Downstream?
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.
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Brought to you by 1AAuto.com, your source for quality replacement parts and the best service on the Internet.
Hi, I'm Don from 1A Auto. I hope this how-to video helps you out, and next time you need parts for your vehicle, think of 1AAuto.com. Thanks.
In this video, we are going to show you how to replace the downstream O2 sensor on this 2003 Nissan Altima with the 2.5 liter, 4 cylinder engine. The items you will need for this are: the new downstream O2 sensor from 1AAuto.com, flat blade screwdriver, and 7/8 inch O2 Socket and ratchet. Depending on the condition of your vehicle, you may also need: wire cutters, and a 7/8 inch socket, just the regular one.
Your downstream O2 sensor is right here and connects right here with the blue harness clip. You want to pull that off that bracket, push the tab, and disconnect the harness. Put your O2 socket on to that O2 sensor and you want to just remove that. In some cases the sensor's in there too well and the O2 socket can't do it. So what you need to do is: you are going to have to clip the wires and use a regular 7/8 inch socket instead. So, like I said, if it doesn't come out, you just want to use some pliers or wire cutters and just clip those wires, pull them off. Now, using a 7/8 inch regular socket, you can just remove that O2 sensor. Use a piece of pipe or breaker bar for leverage if necessary. Then we'll fast forward as Don removes the O2 sensor the rest of the way.
On the left, is the old O2 sensor; on the right, is the new one from 1A Auto. You can see that they're identical. They will plug in and connect exactly the same. Run your new O2 sensor down into place and just twist it in. We'll just fast forward as Don twists that in the rest of the way and then, using the O2 socket and ratchet, tightens it up. Then reconnect the harness and just clip it back on to that bracket and you're all set.
We hope this video helps you out. Brought to you by www.1AAuto.com, your source for quality replacement parts and the best service on the Internet. Please feel free to call us toll-free, 888-844-3393. We're the company that's here for you on the Internet and in person.
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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.
