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How to Replace O2 Oxygen Sensor 02-06 Nissan Altima

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  1. step : Removing the Oxygen Sensor (0:43)
    • Disconnect the oxygen sensor wiring harness
    • Remove the oxygen sensor with the oxygen sensor socket and a ratchet
    • If the oxygen sensor socket does not work, cut the oxygen sensor wire with wire cutters
    • Remove the oxygen sensor with a regular 7/8 inch socket
  2. step : Installing the New Oxygen Sensor (2:11)
    • Put the new oxygen sensor into place
    • Thread the oxygen sensor in by hand
    • Tighten the oxygen sensor with the oxygen sensor socket and a ratchet
    • Reconnect the oxygen sensor wiring harness

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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 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, 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, 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.

Tools needed for replacement:

    Pliers, Cutters & misc Wrenches

  • Wire Cutters

  • Ratchets & Related

  • A Piece of Pipe (for leverage)
  • 1/2 Inch Breaker Bar
  • Ratchet

  • Screwdrivers & Related

  • Flat Blade Screwdriver

  • Sockets - SAE

  • 7/8 Inch Socket

  • Specialty Tools

  • O2 Sensor Socket

2002 - 2003  Nissan  Altima
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2003 - 2006  Infiniti  G35
2006 - 2006  Infiniti  M35
2003 - 2006  Nissan  350Z
2005 - 2006  Nissan  Altima
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2005 - 2012  Nissan  Pathfinder
2004 - 2009  Nissan  Quest
2004 - 2007  Nissan  Maxima
2012 - 2015  Nissan  NV 1500
2012 - 2015  Nissan  NV 2500
2012 - 2015  Nissan  NV 3500
2005 - 2012  Nissan  Xterra
2009 - 2012  Suzuki  Equator
2002 - 2003  Nissan  Sentra
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