Does anyone have any part numbers or a set up used for a post cat O2 space?
All the ones I see and read about are for 18 MM bungs, but the post cat O2 sensor is a 12 MM bung? Cant seem to find pieces to make one up.

 

Must be in the cat rather than pipe. I wondered the same about my96. Plug it and have a shop weld another into the pipe?

 

I have the high flow Magnaflow cat, it is in the cat assyembly in the pipe just after the cat. Dont remember where the stock bung was, but it was the same size, 12MM 1.5.
I guess if one wanted to do this, you could get a bung from a muffler shop, weld it to a short piece of pipe and weld that to the pipe, plug the stock bung. All that effort and I could just get a new CAT! LOL

 

Joel at O2spacer.com has the 12MM spacers for $25 shipped, just not on their site. ordered one. will let the org know if it works.

 

Installed the spacer, drove for a while and the OBDII set the cat monitor to complete, no codes.

 

what is the spacer for?

Is it to kinda move the o2 sensor away from the exhaust flow?

 

Yes, it moves the sensor out of the direct exhaust stream. Lots of them available for 18MM and you can make one up easily, but not for the 12 MM version in our after cat.