ho0n

The bad smell is most likely sulfur mixed in with your exhaust gases. The catalytic converters have probably fouled, but that may also be due to a faulty sensor as well. I would really recommend running some diagnostics on your car with an OBD-II reader to see if your car has flagged any issues before you go about "fixing" this. However, if the gas that's available in your country already has high sulfur content, you will continue to have the smell if you remove your converters altogether.

Eliaquim

Yes I ran an OBDII scan and I have P042 and P043 error codes, referring to catalytic converter efficiency. I did a pressure test, but the gauge did not move at all, which made me believe the catalytic converters' material has been removed by the previous owner. Still have to check this to confirm, though. I am thinking about buying those converters that can be welded, which would be cheaper on shipping. Now that you tell me about a faulty sensor I am worried because I just replaced the downstream (B1S2) sensor. I have to import parts, so I must be sure of what to do next.

Thank you!