I put a Racing beat catback on my P5 last week and there is a LOUD clicking noise after I turn the car off with approx 10 second pauses between clicks coming from the 2nd cat area only after it heats up! Would this be normal? It sounds like the exhuast is(heating up) expanding and contracting(cooling down) if this makes sense to anyone? I checked all of the connections and there is no leaks. Should I be worried?????

 

YOU hit the nail on the head with your conclusion...its the system cooling down....nothing to worry about.

 

Thanks Sir Nuke!!!!!