1995 Celica LE

I have a 95 Celica LE with about 199,000+ miles. I'm the second owner. The first owner, my aunt, got the oil changed every 3,000. I have kept up with that routine. All major repairs have been done at the dealership where it was bought new. It runs great except it started making an odd noise. It's a metallic fluttering/ticking which only happens once I get to about 3100 rpms, and stops around 4100 rpms. The idle is occasionally rough, but if I tap the gas, that goes away. Otherwise the car is in great condition. I don't believe I have lost any power to the car. Does anyone know what might be the problem at 3100 rpms?