Hi all,

Has anyone run into the problem of their catalytic converter honeycomb sliding into their secondary oxygen sensor?
The moving honeycomb still seems to be in one solid piece.

I'm thinking of:
1. Making 4-5 dents outside the converter to keep the honeycomb from sliding into the new sensor.
2. Drilling out a spot in the honeycomb so that it doesnt come into contact with the sensor.

Will it be okay to drive without a secondary oxygen sensor?
My car is running rich, and it is stock aside from a K&N air filter box.

Thank you!

 

One spark plug spacer on the o2 will protect it from the cat media for life.

Use a sheet metal screw to pin the media in place.

 

Hi Billman,

I appreciate your quick response, thank you.

What is a spark plug spacer? is it like a washer that usually comes on spark plugs?

Do i drill a sheet metal screw into the catalytic converter from the outside to hold the honeycomb in place?

Thanks!

 

Look up spark plug antifouler. People use them a lot to pull the secondary O2 out of the flow a bit to get rid of CELs from having no cat or from having some high flow cats. But they serve this purpose as well. Their original intent is for use preventing oil fouling on plugs in a car burning lots of oil, but they work well for this type of thing.

There are also spacer washers that can be used as well. Billman may be referring to those. I am not sure how much spacing is required to pull it out of the flow enough but I suspect either part would work assuming one of the washers is enough.

 

One defouler is all you need. o2 screws into defouler, defouler screws into cat.

Yes sheet metal screws from outside.

 

Thank you Engifineer and Billman. Really appreciate your help.
i've screwed the media in place. There was some dried cardboard? looking stuff when i took off the heat shield from the catalytic converter. do i need that stuff? its turned into dust.
Also, my car is pretty much stock aside from a K&N box air filter. There is a lot of soot in the cat and exhaust tips.
Is this normal?

Thank you!

 

I better add a spacer on mine too. The rear OEM o2 sensor is like $300. Yikes!

 

yikes. I thought they were cheaper than that.
was planning to get a Denso 234-4601 oxygen sensor. theyre only $40ish USD on amazon.
mines a 1999 ap1 though

 

Yeah go with the cheaper one if your rear (secondary one) o2 sensor is broken. The purpose of the rear is just to check to see the catalytic converter (not that big of a deal other than emission). The front sensor is important for engine performance as it monitors a/f ratio.

 

could that be why my car is running rich? it only started running rich a year ago. I burn a lot of oil when i use valvoline for some reason. barely any oil when i use castol edge. same weigh. not entirely sure why. Want to keep the car stock to preserve it. I have a K&N air filter at the moment, want to revert back to stock but it might restrict more air making it even richer.