After 20,000 miles of trouble-free operation and impressive performance since the rebuild, I am hearing what sounds like timing chain rattle from the front of the engine. It occurs generally under very light throttle applications and sounds like my old truck did after the guides started to fall apart. Inspection with the valve cover removed revealed intact metal guides. I know the tensioners sometimes fail after several thousand miles due to improper mounting bolt torque. Will a failed tensioner allow the rattle I am hearing? Is there anything else I should be checking?

Thanks,
Isaac

One other thing I'd check before opening the TC cover would be the oil pump. Check your oil pressure out. If it's too low them this may be it.