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O2 Sensor -- How to change it?

03-27-2007, 06:21 AM
Can anyone tell me how difficult it would be for me to change an O2 sensor on my 1996 Corsica? It's a 4 cylider.

And if this is something a novice can do, how do I do it?


Blue Bowtie
03-27-2007, 06:38 AM
Welcome Aboard!

Unplug the four-wire electrical connector; Unscrew the old sensor; Screw in the new sensor; Reconnect the electrical connector.
If you can change a spark plug, you can change an oxygen sensor.

The trouble usually begins when you attempt to remove the old sensor. It helps a lot to apply penetrating oil to the sensor threads a few days before removing it. Every time you stop, apply more penetrating oil. Especially apply it overnight. Driving the vehicle will tends to burn most of it off, but the thermal cycling will also help it wick into the threads better. When you are ready to remove it, unplug the connector then start the engine and allow the exhaust pipe and sensor to get hot. It will be a lot easier to remove that way.

Apply adequate anti-seize compound to the threads of the new sensor before installing it.

03-27-2007, 06:42 AM
Wow. That's it?
Do you know where I can access a diagram of where the O2 sensor is -- exactly. I am a numskull when it comes to cars! :icon16:

Thanks for the help!

03-27-2007, 07:30 PM
You will need a special socket, as these have a wire on them. Can't use a regular socket on them. But, the socket is cheap to buy and I am pretty sure Advance will loan you one. (they have used tools they "loan" that you basically pay for then get your money back when returned)... the socket looks like a spark plug socket but has a slit in the the length of the socket. Usually these are between the passenger side header pipe and your catalytic converter.

03-30-2007, 11:39 AM
If your changing the front 02 sensor, that should be a one wire sensor. Look down between the engine and firewall, at the exhaust pipe, you should see it.

As far as an old high-milage 02 sensor, you might need a deep six-point socket in order to break the sensor loose. I have used a deep six-point 7/8 socket to remove that sensor, worked ok. I cut the pigtail wire off the old sensor, just to get it out of the way. I wasn't going to reuse the old thing anyway.

When installing the new sensor, I start the threads by hand and then snug it up with an open end wrench, haven't had any problems. There might be some applications, when installing the new sensor, that you just can't reach it, so you might have to use an 02 sensor socket, but, I have replaced several, on different vehicles, I haven't run into that problem yet. I have an 02 sensor socket, haven't used it to install a new sensor, yet.

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