How to remove O2 sensor from Cat?

[aeam1990]

Hi,
I do not have any tools that will fit inside this heat shield to remove the O2 sensor from the front bank Cat. What have you used to remove it?

 

[Spoolinfool]

I can't see what the top looks like but you should be able to use an extra long 02 sensor socket .Use a map gas torch and heat up the 02 and it will break loose easily.

 

[aeam1990]

I was wondering if there was a special socket. Thank you!

 

[edvc520]

On my 1990 964, I tried to change the down pipe myself… the 35 yr old O2 sensor basically seized .. I was stripping my wrench essentially
I gave up and brought it to my mechanic… he used wd40… fire… nothing worked…
He suggested I should order a new sensor for the new down pipe instead… otherwise he will break the sensor

 

[TANTO]

I tried to find an actual 22mm oxygen sensor socket awhile back and ordered what i thought was a dedicated 22mm one and it came as 7/8"/22mm which is exactly the same as the 7/8" i've been using for decades. Theoretically a 22mm would be about .020 tighter which would be nice, but the 7/8" works fine - any parts store should have them - i wouldn't get the extra long one as the standard ones are pretty long to start with (can't have too many tools though). On another car that was badly rusted i once cut a small piece of brass the size of just one socket facet and stuck in on the inside of the socket with double face tape - tacky but works. Caution - it's very easy to get the socket a bit cock-eyed and of course be careful not to damage the wires. And right away wrap the electrode end with dry towels and blue tape the heck out of it to keep it clean - don't even wipe off the electrode. And just a tiny amount of any type of anti-seize. From the look of your parts you shouldn't need to use heat. Sensor antidote - i once replaced a toyota sensor(on a toyota) with a Bosch replacement (Bosch good stuff, right?). Had a hell of a time finally figuring out that the Bosch units spec's were just enough looser than OE to cause issues. Personally i'll always go OE now on most things.

 

[aeam1990]

I tried to find an actual 22mm oxygen sensor socket awhile back and ordered what i thought was a dedicated 22mm one and it came as 7/8"/22mm which is exactly the same as the 7/8" i've been using for decades. Theoretically a 22mm would be about .020 tighter which would be nice, but the 7/8" works fine - any parts store should have them - i wouldn't get the extra long one as the standard ones are pretty long to start with (can't have too many tools though). On another car that was badly rusted i once cut a small piece of brass the size of just one socket facet and stuck in on the inside of the socket with double face tape - tacky but works. Caution - it's very easy to get the socket a bit cock-eyed and of course be careful not to damage the wires. And right away wrap the electrode end with dry towels and blue tape the heck out of it to keep it clean - don't even wipe off the electrode. And just a tiny amount of any type of anti-seize. From the look of your parts you shouldn't need to use heat. Sensor antidote - i once replaced a toyota sensor(on a toyota) with a Bosch replacement (Bosch good stuff, right?). Had a hell of a time finally figuring out that the Bosch units spec's were just enough looser than OE to cause issues. Personally i'll always go OE now on most things.

Thank you! The other sensor came off really easy so fingers crossed on this one.