Rattling post 2000 rpm in every gear

I own a 1999 ford contour sport. It has 140,000 miles on it. After a 400 mile trip, I started hearing a rattling sound coming from the engine area. It starts rattling (a sound like a helicopter or like when people imitate purring with their tongues) when I reach 2000 - 2500 rpm in every gear, under those 2000rpm, there is no abnormal sounds. The sound gets faster as the rpm goes up, in higher gears its difficult to hear over traffic sounds and such. When I take my foot off the gas, the sound goes away, even if still post-2000rpm range. What’s going on?

The noise you hear may be the early signs of a timing chain/guide system going out.

Tester

Any repair would cost more than the car is worth. I wouldn’t bother fixing it or driving it. You have reached my Taurus/Tempo disposal mileage. After 140,000, I consider it to not be worth keeping even if it is running well.

could be something as simple as a loose exhaust heat shield