Clio 203 pop and bangs

[Cjirider1991]

I am thinking of making the modification of pop and bang to my Clio but my tuner chip tells me that it is not recommended. How could it affect the car?

 

[Sean197]

The pops and bangs are unburnt fuel going into the exhaust on overrun, which ruins the catalytic converter.

 

[MattP]

The pops and bangs are unburnt fuel going into the exhaust on overrun, which ruins the catalytic converter.

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