Rattle from engine bay at certain engine speed (2600rpm), when autoblip at mid to high rev and when the engine is about to stall. The sound is like metal hitting metal. At first I thought the rattle is from the vibration of the exhaust. Have the car checked at the dealer but nothing was found.

Recently I’ve installed the Cargraphics catback and silencer. The mechanic has checked to ensure nothing is touching the exhaust. The rattle still exists.

Does anyone here have the same experience? Any advise on how to resolve the problem?

 

I have a similar sound, l'm pretty sure it's the knock sensor kicking in.
It's been happening on and off for over 2 years. It's nothing to worry about and It doesn't really concern me.

 

I had the Cargraphics Cup exhaust and you could hear a little rattle at low revs when getting off the throttle...sounded like metal or a heat shield but was in fact the exhaust, never found the cause. Changed to the GT3 conversion and its' gone.
It wasn't a big thing for me but still a bit annoying when bliping the throttle, car stationary, and when the revs dropped to 2500-2000 you would hear it and then it would be gone at idle.

 

I had a very strange rattle after doing a swap from cat delete back to cats on my Cargraphic sport headers. Figured out it was the metal gasket between the exhaust pipe to header pipe. I had reused it at least 3 times. Replaced it with new and rattle was gone.