Peugeot Repair Questions? Ask a Mechanic for Answers ASAP
Hello, my name is Mark and I will try help you with this.
This type of sound can be normal for a new exhaust. It can take a while for the exhaust to carbon up inside and deaden this noise.
However, to be on the safe side you should take it back to the garage that fitted it for a second opinion but I'm sure it will clear in the next few weeks.