Strange Noises

[KenC]

A few days ago, I noticed that my engine, under load (doesn't do it at idle), was making noises as if there was a handful for quarters under the hood.
I popped the hood and pinpointed it to where the timing chain tensioner is, at least the front left portion of the engine (if you were looking straight at it).
I put a new timing chain tensioner in and the noise is still there.  After this, I naturally I suspect perhaps one of the guides has broken or something, so I rip the entire front portion of the motor off and see nothing out of the ordinary.  Yes, my gears are a little worn, but all of the rails/guides look just fine.

Any ideas as to what could be causing this noise?

[EN318isPDX]

Water pump? Maybe a little slack in the chain?

[KenC]

What sort of noise would the water pump make?  I don't think the noise could have been made by it.

Would chain slack be gradual?  The engine sounded totoally fine one moment, and then terrible all at once.

[EN318isPDX]

What sort of noise would the water pump make?  I don't think the noise could have been made by it.

Would chain slack be gradual?  The engine sounded totoally fine one moment, and then terrible all at once.

A water pump either grinds or sounds like a bearing squealing. You said it sounded like quarters so I was thinking it might be the chain tapping up against something.

[KenC]

I was thinking the chain too, but everything looks fine and the tensioner is brand new.

[nicknikolovski]

What sort of fuel are you using in car? If you use less than minimum requirement, the engine will ping (knock).  It will sound like marbles rolling or a metallic type knocking under load.

Maybe post a video or audio sound if you can?