I've noticed a weird metallic rattle at idle. I thought it was just the exhaust or a heat shield. It got noticeably louder and I stuck my head under the car to see where it was coming from. It was coming from the catalytic converter area, but when I put my foot on the cat to stabilize it the sound continued. I also found tiny white flecks coming out of the exhaust. Removing the cat today, I see that my 3" hi-flow cat is not living up to its name:



The rear section of the honeycomb broke free and turned sideways. It almost completely blocks the outlet. I bet the car is going to run a lot better with a new cat.

Corbin
'97 GSX dressed like a '95 ESi

Was it a name brand cat or an eBay special? Mileage/age of the cat? I know you have emissions of n your area, but maybe a drop in test pipe for the other 364 days of the year is in order :)

+1 on a test pipe, no question about it!

That's a new one! Sounds like a drop in performance wasn't what you noticed initially, that's crazy because it's almost entirely blocked.

It was a Magnaflow cat that I've had about 8 years. I've had good luck with that brand with mufflers, but I am disappointed with the cat failure. It might have seen a little more vibration than a stock vehicle, but not abuse. I bought the identical part number again and will hope to get at least 8 years out of it. I do need to pass emissions. I am also a closet greenie.

Corbin
'97 GSX dressed like a '95 ESi