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Removal of front O2 sensor - need advice


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2000 OBW, 4 cyl, automatic. I need to remove the front O2 sensor. Can someone suggest in very specific terms how to approach it, i.e., from the side, from the front, etc. Yes, I have used the search function. Yes, I have the 22mm offset O2 sensor socket. But I simply can't figure out the proper angle of approach. I had this same problem with removing the lower nut on the starter until I had a eureka moment and it was incredibly easy. Not having the same luck now. TIA.

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Start soaking it down now.

 

Amen.........on soaking it down first. I used PB Blaster, waited a day to put a wrench on it. It is really necessary to lift the front end up in the air, so you can get underneath the car. I use drive up ramps to accomplish this. When I swapped out my 02 sensor, I bought an 02 socket with extra wide offset from a parts store. It worked really well. Use a breaker bar with an extra long handle to get extra leverage to break the sensor loose. Pull down slow and easy, you don't want to break off the sensor by jerking on the handle.

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HEAT is your friend. Get the exhaust hot first by running the engine for a few minutes. And you'll want a big hammer to smack the end of the wrench with to get it moving.

Every time I've used one of those sockets it was a waste of time. It just expands and slips around the sensor.

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Just drop the y-pipe and get the correct special O2 socket. Sometimes you can indeed get at it with a 7/8" open end wrench - but often you can't because of the heat sheilds. Drop the y-pipe down, take it out with the socket, and be on your way. Really not a difficult job. You do need a quality socket. If it's really buggered up in there you can break/cut the end off the sensor and use an impact.

 

GD

Edited by GeneralDisorder
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if you are committed to removing it you can cut off the wires at the sensor and use a BOX END 7/8 wrench. it grips well, will not spread so it can't slip and since you are throwing the sensor away you do not need the wires. but i have doen the same thing by feeding the wires thru the ''box'' of the wrench.

 

pblaster is a must. warming the exhaust up is good too. just don't burn yourself.

 

i'm not sure which is better, banging with a hammer to get it starter or strong steady pressure. i'm a fan of impact wrenches so it a tap or 2 with a hammer to get started.

 

on reinstall, you need it tight enough to not leak but it does not need to be as tight as it was when you removed it.

 

on a side note, i used too much force and not enough pblaster or heat on a 96 exhaust that was off the car and i twisted the bung out of the converter / exhaust. not a big repair but avoid this if you can.

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