Catalytic Connverter

Had a check engine light on my K5 Blazer and found it to be an oxygen sensor. Installed a new one and cleared the code and headed down for a California smog inspection. My vehicle failed because the code was just cleared and the Dmv computer knew it. The smog man told me to run it through some "cycles" meaning go do some errands, start stop, turn it off start it up drive for awhile. Maybe 5 of those he said. i did ,went back and it passed.
Your results may vary. As far as running your vehicle without a cat on it....hhmmmm....not sure what effect that may have. Mr know it all will chime in and let you know......