note: I was not able to find what I was looking for while doing a search

I have heard from someone who has a paid membership with Scion support that only about 1 in 4 O2 bungs in the manifolds for the tC had any antiseize used, therefore many of the O2 sensors that are being removed have had their threads stripped. Requiring a new $200+ O2 sensor.

I have researched a few different ways to safely remove the pre-cat "Wideband" O2 sensor and was wondering what your experiences have been.

Technique 1:
Removing the O2 Sensor
a. Using Q-Tip or your preferred applicator lube the thread/attachment area where the O2 is screwed into the downpipe with Liquid Wrench, PBlaster etc... Give it a few minutes to set in, lightly tapping the area you applied it to helps it penetrate.
b. Using preferably a long handled socket wrench (for leverage) and an extension with an 'O2 Sensor Socket' attachment.
c. Pry loose.

Technique 2:
First you need to wait till the engine is 100% cooled off, then spray liberally with liquid wrench, PB Blaster, etc. Wait about 30 minutes and give it a crank.

Technique 3: Same as Technique 2, except run the engine till it gets hot instead of being cool and repeat the steps above in Technique 2.

Technique 4:
0) Try to tighten it first.
1) Use some sort of bolt breaker spray (lubricant)
2) Get a huge breaker bar
3) Heat the o2 sensor bung with a blowtorch
3a) Do it while the exhaust is still hot from driving
4) Gently cool the actual O2 sensor itself. (Compressed air can unpside down or something)
4) Smack it with a rubber mallet (good luck, last resort lol)

OK, the most interesting thing I've researched to remove these sensors is to try and tighten it first. Once you get a wrench on it, crank on it as if you were tightening it, you'll hear the threads breaks loose. Then start unscrewing.

The reason this may work is because the last direction the O2 sensor threads were going were clockwise, so maybe the molecules that get stretched while tightening become attached to the o2 sensor threads.

This is supposed to be the oldest trick in the book, yet hardly anybody knows about it.

 

whoa dude. chill

it's not hard. if you're removing the O2 sensor (after cat) you should have even less trouble than if you're doing the air/fuel ratio sensor (pre cat)


here's all you gotta do:

MAKE SURE THE CAR IS NOT HOT!!

this is why they all strip and get ____ed up. at work we always let them sit as long as possible.

so attempt this on a morning after an overnight sit for example.


get a 7/8 or 22mm (same size) wrench. these are usually about a foot long. this is to your advantage.

unplug the sensor. slip the box end (the circle part, not the crescent) over the wire. put it around the sensor,

i always jerk rather than slow pressure. give it a good crack. it should come right out. i rarely ever have problems.

threading the new one is easy. tighten it like a spark plug, slightly more than snug. plug it in. the end


you really shouldn't have any trouble. just remember: CAR NEEDS TO BE COLD

 

What are you doing Marshall? Are you putting in a turbo?



You better not get yours before me. I got mine confirmed today...going blue. This is gonna rock

Yup, TCTech is right. Cool is key and just crack it loose.

 

Don't worry, I'm at least a batch behind you.

Thats going to look so nice with how you already have your engine bay setup:


Yes, this is what I thought. However, other pro mechanics... like yourself have said hot. That is why I am interested in what the pro's have to say about it. Any and all opinions are appriciated. There have just been so many of these stripped when removed from a tC manifold. When the time comes, I want to be ready :D

 

What I've mostly heard here on the boards is to let it cool, then give it a good soak in WD-40 before you try to remove it.

Not that I'm an expert on this sort of thing by any means, just passing along what I've read.

 

Well, I know everyone says to do it COLD, but I recall doing my head back in Feb, I did it warm to cool. I let it cool down enough to work with it and didn't think twice about it. I didn't use WD40 or nothing. Frankly, pulled the car in, waited for it to cool down enough to not burn me, and started taking it apart. The 02 I just put a wrench on it and cracked it free. I asked my brother who does this for a living and he said just wait for it to cool down and go at it.