knocking sound (or pinging) is very hard to describe.
if you can hear a metalic sound or if it sounds like "shaking a can of sand/marbles" or a rattling sound ...when u accelerate your engine, then your engine is knocking.
something to share ..i have a pic for both housing..can compare side by side...this is an OE housing...just our work of machining..so.. enjoy...or any comment / idea are most welcome :proud: