I have a 1989 CRX si with a SOHC ZC Vtec motor, full thermal research catback exhaust, stock cat (replaced about 3 years ago) and DC sports 4-2-1 header. When I got the exhaust about 1 year ago it was nice and quiet and now it is very loud (5x louder). I removed the cat. converter today and I can still see the mesh. I am wondering if there is something wrong with the cat (even though it looks alright) or something wrong with the muffler? Any help is appreciated!

-Jason

 

look for holes. One of the hanger welds broke on my old Thermal and it put a hole in the pipe.

 

Check for leaks. Start the car in the air on a lift or jackstands and run your hands along the full length of the exhaust, and where you feel hot air blowing is your leak. make sure header bolts are still tight while your at it.