Perhaps you've been a victim or savior of something like this and have more of a clue than I do...
My car recently had both heads replaced, new timing belt & tensioner kit too. It has 140k on it.
This morning it starting this terribly loud knocking.
It sounds just like this guys' video.
Any Idea? Piston slap? Rod Knock?
After all the work I've had done on it, I'm about at my wits end.
JCB