Hello everyone. I'm about to help my friend install his header and I was wondering about the removal of the O2 sensor. From what I've read on the tC forums and all, it is cross threaded (and on purpose as well). This isn't really a good thing, so I wonder how you guys went about this. There are way too many different pieces of advice out there, so let's get them in this thread. The idea I had was to let it be completely cool, spray some WD40/whatever in the threads after loosening it a little bit, then tightening it and letting it sit overnight, then trying to remove it. Although I hear some people say it is better to warm the car up, but won't that "soften" the metal and make it easier for the threads to strip?

I don't want to mess up my friends car, so let's try to make this a painless install. Any advice? For the record, he owns an xB2, not a tC, but that doesn't really matter anyway.

FWIW mine came out easily with a 22mm (or 7/8") open end wrench. It certainly wasn't cross-threaded and I don't believe they are ever intentionally installed that way. Sounds like web-myth to me.

I'd spray some WD40 or PB-Blaster and give it a try. If you can't break it loose, spray it again and let it sit for some time. If it's stubborn, the plug fits thru the closed end of the wrench. If it's really stubborn like my secondary O2 was, you can heat the bung with a propane torch or whatever you have on hand and keep trying. If it still won't budge it may be time to buy a good O2 socket (not the cheap junk most buy and break) and use a breaker bar.

Be sure to use some anti-sieze so you won't have any trouble next time. Good luck.

x2 on PB Blast,should be in every gearheads garage anywhays

Good stuff to know. I have all the necessary tools, except PB Blaster, although I do have WD40. We'll see how it goes. Thanks guys.

wd40 will work but consider buying the pb blast anyways, it penetrates better and workes like wd40, stuffs pretty cheap anyways

wd40 will work but consider buying the pb blast anyways, it penetrates better and workes like wd40, stuffs pretty cheap anyways

I planned on buying it after doing some reading. I don't really care about the cost (although I am aware its cheap, haha), cause I'm sure it'll definitely be useful in the future.

FWIW mine came out easily with a 22mm (or 7/8") open end wrench. It certainly wasn't cross-threaded and I don't believe they are ever intentionally installed that way. Sounds like web-myth to me.

I'd spray some WD40 or PB-Blaster and give it a try. If you can't break it loose, spray it again and let it sit for some time. If it's stubborn, the plug fits thru the closed end of the wrench. If it's really stubborn like my secondary O2 was, you can heat the bung with a propane torch or whatever you have on hand and keep trying. If it still won't budge it may be time to buy a good O2 socket (not the cheap junk most buy and break) and use a breaker bar.

Be sure to use some anti-sieze so you won't have any trouble next time. Good luck.

I just sprayed the hell out of mine with PB Blaster and let it sit for about ten minutes. Then just use put a wrench on it and make sure you can get as much leverage as possible. Mine was NOT cross threaded.

I always used Liquid Wrench and then a bunch of people on an Eclipse Forum said I should use PB Blaster and it was much better. So, I bought some PB Blaster and as far as I can tell it's an excellent example of good marketing resulting in every "gear head" buying it. However, I got better results with the Liquid Wrench -- now the PB Blaster just sits there in its heavily marketing decorated can -- can't imagine ever using the rest of it!

trevor

my o2 sensor was not cross threaded either,
but the threads on my strup header were not the same thread i had to chase the threads on it

my tc's o2 sensor was not cross threaded either.
I took it out and reinstall it many time.

I used a adjustable wrench and a lot wd40.
When i replace my o2 sensor at the spipe, i notice the new sensor comes with some anti-seize on the thread. I would suggest putting some on the threat when u reinstall the sensor.
I always put anti-seize on the wheel lug nuts threat.

Anti-seize is great for engine and brake bolts too.