How to Replace Downstream O2 Sensor 2005-11 Honda Civic

Hi, I’m Mike from 1A Auto. We’ve been selling auto parts for over 30 years!

Secondary O2 sensor is further down here in the cap. Follow the wire up, it's connected here to this bracket. You actually need to disconnect the body side of the harness first, so I'm going to reach down and there's a lock on the top. Pull it up. It's going to get stuck sometimes. Put that aside and this harness is clipped to the bracket.

There's a lock on the backside of this, so I'm going to push it in towards with connector and then just with my thumb push the connector down and work it off the metal bracket. Just like that. If it happens to break off or you can't you get it free and you just break it at the end, the new one you could zip tie to here. You just don't want it flopping around. The wire's disconnected.

We can slide our O2 sensor socket down into here. I've got a breaker bar on it. A little tight with the fans in place. There I got it in place. I'm going to remove it. That broke free. I'm going to take the socket out of there. I'm going to reach down with one hand, in the other hand I can hold the wires and help them spin. I'm just going to thread it out by hand. I'm just going to thread it out and pull that out. There's our O2 sensor.

We're going to reuse this O2 sensor because it's working just fine. You might be doing the same if you were just changing the catalytic convertor. We just want to show you how to take it out so we're going to add some copper anti-seize, right to the threads only. You'd do the same if you're installing a new sensor.

I'm going to carefully reach down you can just see the opening in the catalytic convertor. I'm going to thread it in place just with my hand. I just want to feel it thread it in there so I don't cross thread it. Now I can take the spark plug socket and a ratchet, we'll slide it down in there. Take a couple turns. It'll get tight and that will o-ring seat the crush gasket will seat. That feels good.

Get the socket and ratchet out of here. Can run our wire back up the harness. I'm going to clip it back into the bracket. Reconnect our body side one. It'll click together when it's locked. That's how you replace the O2 sensor.

Thanks for watching. Visit us at 1AAuto.com for quality auto parts, fast and free shipping, and the best customer service in the industry.