Its a 1996 nissan sentra with the 1.6L engine.. i forgot to add!

Most engine knock sounds that are due to wear mostly get quieter when
accelerating as the loading takes up the play, so I don't think it's
bearings or a worn piston skirt or bore unless someone has experience of the
problem with your engine specifically.  I've known it though just before a
crankshaft snapped in half but that's so unlikely forget it.

Perhaps it's heavy pinking, that can sound like a light tinkling if it's
only just doing it but like a hammer on an anvil at its worst and will be
much worse when accelerating especially if the engine is hot.  I doubt if
the oily plug  is relevant unless it's causing pinking (unlikely).  Ignition
timing too advanced, wrong fuel grade, weak mixture, wrong plugs, lots of
carbon in the combustion chamber can all cause pinking.

Sometimes it's just something loose somewhere like exhaust heatshields, or
engine mounts too floppy.

I would have the plumbing to the "E.G.R. valve and the valve itself"
looked at it could be blocked-up with carbon and still run without
E.G.R. flow. also find a shop that can de-carbonize your engine they"l ru
the engine on a concentrated cleaner that flushes fuel injectores and also
de-carbons the combustion chamber

--
johnin