The cat on my car just started making an awful rattling noise today and when I shake it I can hear something rolling around inside. As its the cat that has been with the car for the last 160k I wouldnt be surprised that its dead now. (also got a pending P0420 code when I plugged in the reader, which goes along with me thinking the cat is falling apart) Im not planning on leaving the car catless permanently but because of the situation im in right now (will be moving for a summer internship shortly) I would like to pull out the cat and clear it out so I dont have that rattling noise/loose bits of the honeycomb blocking up my exhaust. This would just be until I move in to my internship apartment and can get a replacement ordered and installed. I know people will say its a bad idea and whatnot but the way I see it I either have no cat or I have chunks of cat rattling around my exhaust system. Is there a way i can prevent the code that will show up when the downstream O2 sensor sees that there isnt a cat? I know that on some cars you can buy a spacer to get the sensor out of the stream but i dont know if theres such a thing for this car. If there isnt how much would I have to have the sensor offset for it to read the levels it needs to think the cat is still there? Any input is appreciated. (I have the 2002 C230 coupe with the M111 engine and only one cat if that helps)

You can or used to able to buy an afermarket cat for $100-200 for Walker brand.
Things cost more now, so no idea on cost nnow but cheapest way is to buy it and find a
muffler shop to weld it in for around ~50.
Cheaper to buy it yourself than from a shop.
I tried the spacer thing, didm't work. If you meed to pass smog
you're gonna need a new cat period.

Ive got a welder so thats what Ill do, I dont need to pass emissions or anything so Ill probably just deal with the CEL until I find the reason the first cat went bad. it maybe was just age but the last few times ive looked at live data on my obd scanner it was adding a little bit more fuel than id expect so I think there may be some other business afoot with the fuel system. Never found the source of the CL fault with the fuel system so ill probably have an indy look at it just for their two cents. Ill have to fire it up once I knock out the cat to see how loud it is, probably gonna sound awful since its a four cylinder but I still want to see what its like for the fun of it

well I cut open the cat to get the loose stuff out and uhhhh, this is what I saw when I opened it up. Im a bit confused as to how I wasnt getting a CEL for this. Well its out now and heres how the car sounds catless without the muffler. Not bad until you rev it then it turns into a fart machine.