02 Sensor

[triplewhite]

How do you remove the 02 sensor? I've had a new one for months now waiting to get around to replacing it, and now I have the transmission out, I thought this was as good a time as any. I just can't get to it and get enough leverage on it to get it off? Is there a trick?

[Calimus]

if you have already removed the protective sheild around the O2 or were lucky neough to to have it at all, it's just a matter of getting at it and having enough leverage to break it free. Keep in mind that it's been heated up and cooled as many times as the car has been driven. That means it's going to want to stay there forever.

There is a product called PB-Blaster that will help eat the rust built up on the bolt connection. Saturate it with the PB-Blaster and let is sit for a few hours, then soak it again and let it sit. Sometimes it can take a few douses and an overnight wait to do it's job. That may loosen things up enough for you to break it free. It's definitly in a PITA location on 8v motors.

Oh, when your done with the swap or if you give up, use water an dilute the snot out of the PB-Blaster sprayed area, if you fire the car up, there is a minor chase that it could ignite. And you certainly don't want that.

[1lowcab]

you just might need the hot wrench on that. good luck.

[Briano1234]

spray PB blaster every 20 minutes for a about 2 hours, then Start the car, and let it idle for 2 minutes, then using the o2 sensor socket, then it's a piece of cake.

[triplewhite]

Thanks all, I'll give it a go!

[tolusina]

I've replaced thousands of O2 sensors in my career, occasionally one comes along that will not come out no matter what, I just happen to own one.
I have a variety of different tools available, leverage was not a problem. I sprayed it with P.B. blaster before and after every drive for about three days, still, it refused to budge, hot P.B. Blaster is not odor free.
I really didn't want to break it off, once I accepted that it wasn't coming out, the solution was simple.
I hole sawed a 7/8" hole in the right side of the downpipe and MIG welded in a bung. Most local muffler shops should be able to do this easily and economically.

Side story, As I shopped various auto parts sources by phone and in person looking for a "Bung", I wearied of the "Why you talkin' nasty" tone and looks. When I finally called the muffler shop that had bungs, instead, I asked for a "fitting". He replied, "Oh, you mean a "Bung".

The 2nd related side story, Once the new sensor was installed in the downpipe, the old sensor remained electrically connected for a day or two, waiting for a round tuit. Being able to simultaneously monitor voltage output signals of both sensors reading the same exhaust thoroughly confirmed how sluggish the old sensor was responding.

[triplewhite]

Cool, thanks a lot... A local german "specialist" told me to just disconnect it and not use it. In fact, after fitting a clutch for me, he disconnected it by pulling the plug off the back of where the speedo cable plugs in without telling me. This, along with a few other reasons, is why I'm doing all this work myself now.

Thanks for the tips! Are you getting to it from underneath the car, or from on top? I can get to it best from underneath right now, but that may just be because I have the transmission out...

[Calimus]

Yea, once the tranny is back in place, it makes getting at it from underneath a real fun job. I've always attacked them from the top side anyway.

[triplewhite]

You must have thin arms, or remove the manifold! Sometimes the Germans are brilliant, sometimes plain stupid. Obviously this was something installed before the engine!