i think my cat is in it's last days my car got significally louder the headers i think are to blame, i just noticed it yesterday and today my bro was like why is it louder then before, i guess my question is should i be worried for my cat?
i think im going to throw on the stock ones back on if the noise gets louder

 

If the cat is going, the O2 sensor will read it and the ECU will let you know with a CEL. Do you have a CEL? As for the louder sounds, maybe you have a cracked header or exhaust system. Maybe you have a big exhaust leak.

 

I installed comtech headers and long ram cold air intake (from comtech] and of course the car is a bit louder. I think most of the added decibels are due to the less muffled air intake than the headers. Whatever, the car has a nice growl now, especially when vtech engages, but not loud at all in normal driving. Check for a swishing sound around the head and where the header mates to the cat. If it is a leak you should be able to isolate it.

 

i say you throw out ur cat and get a test pipe
what xviper said is correct. if you cat is not working properly, you will throw a cel

 

If you validate that your cat is bad, I'll sell you my OE one. Check the thread on my sig. I ended up with a new one as a result of a map sensor mis-diagnosis by the dealer. It has very low mileage on it.