1990 Camry Grinding/rattling Noise

[wuziq]

several weeks ago, i noticed that my car, a 1990 camry lx, 2VZFE engine, started making a weird "grinding" or maybe rattling noise. another thing is that it "oscillates," meaning it goes loud then soft then loud then soft, etc. it's pretty noticeable when i'm idling cuz it's a slow oscillation (it gets loud like every 3 seconds or so), and i can hear it oscillate faster as i accelerate.

i don't know if it stops when i get fast enough that i can't hear it.

i think it's coming from somewhere on the right side (passenger side) under the hood.. at least, that's what it sounds like. i've tried looking under the hood with the car idling to see if there's anything obvious, but i'm a total noob (if u couldn't tell by how i'm describing this problem).. i don't know what to make of it at all.

any help would be greatly appreciated.. i know i'm not doing the best job in describing it, but i'll try to provide as much information if it's needed..

[gazza1286]

Could be the plate over the exhaust manifold - They hava a habit of rusting through around the bolt holes facing the radiator. This allows the plate to vibrate against the manifold causing a metalic sound which will obviously change as you accelerate.