I'm trying to trace a moderate rattle I hear even under light load in the lower rpm range (roughly around 2500 rpm and up). With the hood up and a friend blipping the throttle I heard a bit of rattle from the ACV, but it seemed only after the throttle was released. Not so on the gas. When on the road I hear it pretty much all the time, but it is much louder with the engine cover off. I don't hear it on decel on the road though. I', sure it is coming from the passenger side.

 

u sure its not some water flowing sound ?

 

I recall it being rather buzzy. I'll see if I can get a decent recording.