2000 Civic Metallica Engine Noise at High RPM

I have a 2000 Honda Civic, I have been the only owner. The car has 104,500 miles on it. The engine, upon acceleration, at approximately 3000 RPM will make a metallic noise, whirling, metal hitting metal, in a way, but tinny. Kinda like a box fan when you move it and the arms hit the protective grate.

It only does this if the engine gets to about 3000 RPM and above. So, if you are a stop light, accelerate, the noise starts at about 3000 RPM, the car will then shift to second, as it goes up through the gear, again at 3000 RPM or so, the noise starts. It does up through all the gears. If I'm on the highway and going faster than say 70 or so and the RPM is above 3000, then the noise will be there. If I back off the accelerator in either instance, the noise will go away, returning upon acceleration above 3000 RPM.

It makes no noise if the car is in park or neutral, no matter how high I rev the engine. Only when moving.

The vehicles power seems slightly diminished and it is getting poor gas mileage. This began 4 days ago, that I first noticed.

In March, when the vehicle had 100,000 miles on it, it died in the middle of the road and I took it to the dealer, as I could not restart it although it would crank. They replaced the engine coil to fix the problem. But, I also had a major tune-up performed, as well as the timing belt replaced. This was 4 months ago.

Any ideas? Someone said this sounds like a timing belt issue, but having had that just replaced, I'm thinking more of an exhaust manifold. Or something.

Expense?