Hyundai Repair: 2000 accent black smoke while idle, air fuel mixture, catalytic convertor

Question
I own a 2000 Accent, it did not smoke at all. Recently I removed the interior stuff from the catalytic converter and used a little water to wash off some debree/particles that were left. Right after that a lot of black smoke started to come out from the exhaust while the car idles. It runs and accelerates very well but as soon as I stop at a red light, black smoke starts to come out. I disconnected the battery so that the computer gets new readings from the O2 sensor but didn't solve it. What could be causing the car to smoke so much now? Is it possible that the O2 sensor was damaged because of the water and it is sending out wrong air/fuel mixture readings to the computer? I would really appreciate any help with this issue.

Answer
Hello Marvin,
You should not use water to clean the catalytic converter and you should not remove anything out from it. Catalytic convertor is an unibody part with ceramic honeycomb shape filter inside. If anything comes out off it that means converter is contaminated and should be replaced.Replace catalytic convertor (I highly reccommend OEM part) and see if smoke issue continues. If you still have smoke let me know so we can work on it.