So awhile back I redid my exhaust. before it was header to straight pipe to muffler. I changed it to 4-2-1 header to cat to pipe - muffler. Got my primary o2 sensor on just fine but I the o2 sensor wont fit on the cat. its too big. what are my options? im in jersey so this is just to pass emissions ( the right way this time lol) My header does have a spot for another o2 sensor but im assuming having both the primary and secondary sensors before the cat will still throw a cel? any help is appreciated.

 

just get a new one off ebay for 30-40$ or go to the junk yard. other potion is get a different CAT strange that the thread pitch is different if it was meant for your car,

 

im thinking if I can find a non fouler that fits this smaller o2 bung on that cat i could still make it work. its a longshot but ill look into it. buying a new cat is too much hassle. this one isnt even 6 months old.

 

What do you mean it won't fit? What is too big? Is it a real cat or a test pipe?

 

its a real cat.


doesn't fit the oem denso o2 sensor i bought. the sensor is too big for the o2 bung on the cat

 

go to a muffler shop and have them weld the correct o2 bung into the cat.... probably only cost ya 20 bux maybe alil more