The Nissan Path

Hello I was wondering if anyone knows what may have happened to my 2003 pathfinder. I was driving and the engine started knocking, I pulled over and shut it off and let it set for 10 minutes and started it back up. It knocked and then stopped and it has not done it again and that was 2 weeks ago if anyone has any answers I would love to here from you
Thanks

If the engine overheats it will pre-combust resulting in a spark knock.

I hope it didn't drop a power valve screw!