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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.
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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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're going to show you how to replace the downstream O2 sensor on this 2004 Volkswagen Jetta with the 1.8 turbo engine, and it's the same part and process on these Jettas from '99 to 2005. The items you'll need for this are a new downstream O2 sensor from 1AAuto.com, 10 mm socket and ratchet, O2 sensor tool, flat blade screwdriver, and jack and jack stands.
Your downstream O2 sensor is located right here. You want to start off by just removing this insulation sleeve from the O2 sensor wire, and it just unbuttons. Now, pull the O2 sensor harness from this bracket and then remove these two 10 mm nuts. We'll fast forward as Don does that. Pull the box down and then pull out the harness for the downstream O2 sensor. Then just push on the tab on the harness and then pull it free. This is a short O2 sensor tool, good for tight spaces like this. You're going to slide it onto the wire and up onto the O2 sensor. Then, using a 3/8 inch ratchet, just insert it into that square hole. Then you just use the ratchet as you normally would to loosen it up. You just want to keep using it to loosen it up. Then once you feel it's loose enough for you to remove by hand, you can just twist it out the rest of the way by hand.
On the left is the old downstream O2 sensor. On the right is the new one from 1A Auto. You can see they're identical and they're going to fit exactly the same. Take your new O2 sensor and just twist it into place. We'll fast forward as Don twists that into place and then tightens it up with that O2 sensor tool. Now rebutton this insulation sleeve around your O2 sensor wires. We'll fast forward as Don finishes that up. Now clip your new O2 sensor wire into that bracket, and if it fell down, just reclip it right up here. Reconnect your downstream O2 sensor harness and push it into place. Make sure the wires are coming out through the openings on the sides and then push this box back up into place. We'll fast forward as Don replaces those two 10 mm nuts and tightens them up. When you're done with that, 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.
