Hello, I recently started hearing a loud slapping noise coming from the drivers side of my engine compartment, I initially thought it was a belt about to snap, but being that all the belts are on the passenger side, it didn't make sense. So I started thinking that the internals of the engine are dying. Then started realizing that it was consistent with the RPM's, only happens when accelerating, but doesn't happen all of the time. It's a 2001 Hyundai Accent GL. 100,400 miles on the whole car, engine was replaced about 30-40k miles ago. Anyone have any ideas?