A Catalytic Converter is an exhaust emission control device that converts toxic gases and pollutants in exhaust gas from an internal combustion engine into less-toxic pollutants by catalyzing in a Redox Reaction. 
Overtime, depending upon the quality of fuels and usage, Catalytic Converters get clogged with deposits that need to be cleaned. If they are not cleaned then Following Faults may occur:

  • Declining fuel efficiency
  • Check warning light
  • Smelling Rotten Eggs
  • Issues starting the engine
  • Poor acceleration

Moreover user May have to buy a new Catalytic Converter which is Quite an Expensive Job.