So I'm at my wits end trying to locate (and fix) a loud, high frequency rattle noise inside the engine compartment.
It can be heard when applying the gas pedal a certain amount. In other words, I can "find" the noise and maintain it at a certain rpm.
The noise is coming from the back of the engine near the firewall. It feels and sounds like it's coming from the throttle body plate and vibrating the gas pedal. I cleaned the plate and it isn't loose.
The issue doesn't seem to be affecting engine performance.
Any ideas?
EDIT:
The sound is noticeable while driving (under load). When in park, I can find an rpm where the throttle body seems to take a heavy wave of vibration from the engine and hum (but not nearly as loud as while driving).