I have FI (Turbo) and running rich. My Cat has recently making ticking noises (or it could be the engine I'm not sure) during idle, drive, or anytime my ears are open to the sound. Even after the engine has been off. It sounds like the oil settling after the engine has been shut down but it more rapid and itz coming from the exhaust piping (cat too I think) along with the engine. Only thing I could come up with was that maybe my fuel (that wasn't burned since I'm running rich) is released into the piping and it boils in there. Has anyone suffered major engine damage, etc and remember hearing ticking noises?

Tuner

 

I haven't heard it while driving, but at idle and after switching off the engine the heat-shield on the cat will start to shrink and that make a ticking noise. If that's what you are hearing then don't worry its normal.

EDIT:
BTW. It can also be the heat shield in the engine bay, as you probably know metal expands when it heats up and will start to shrink once its cooling down that's what makes the ticking noise.

 

Is there a way to know for sure? But what you've said definately reassures me. Thanx

Tuner

 

I am not sure you can truely verrify this. But should not hear this noise when you start a cold engine and let it idle.

 

Actually I let it idle till it reachs three bars and it happens the moment the car is started.

Tuner