New cat, now the rotten egg smell?
 

Just replaced the catalytic converter a couple of weeks ago. Car did not smell like this before the change.

I'm thinking that I have a leaky injector and maybe the unspent fuel is causing the smell when it hits the Cat.

Only burning 93 octane name brand fuel, so I don't think it's a sulfur issue.

Any other thoughts beyond the leaky injector(s)?

Thanks for any insight

Was it replaced with a stock cat? Do you have a functional airpump?
I have a stock cat and aftermarket down pipe; before the cat warms up my car reeks.

did you get a high flow cat?

that means the cat is properly working

Still have the air pump, cat is after market from Midas.

does it have that smell all the time or just whe you get on it hard?

Rotten egg smell is hydrogen sulfide (H2S). Has to be sulfur somewhere to generate that. Could be sulfur in the engine oil, in the fuel, maybe a compound in the cat's adhesive. It will burn off if part of the cat; not so much if in the oil or fuel.

could be battery leaking

:icon_tup: Go test drive a new BRZ and floor it. I'll bet you'll smell the same smell. It's the smell of a brand new cat.