"metalic" rubbing sound comming from air filter area

[paradiseincome]

HELP.. i have a stock 2001 2.5 cougar 5sp, in the past month or two at start up and lower rev range 1000-2000 or so, I hear a (best described) metalic rubbing sound/vibration from the air filter area (where the air filter meets the engine) its getting slightly worse as of writing. Has this every happened to anyone before, what do you think it might be, I have owned this car since new, and given proper maintiance, and i dont race (gosh i'm sure some hate me here now) this happens during acceleration and not, in gear and out at a stop and moving, with a/c on and with it off, not related to steering, belts seem to be OK.. i'm hoping its a quick electonic replacement (like an o2 sensor) ANY IDEAS APPRECIATED!

[skater]

Check the battery tray and all that to see if it's tight...

[Gorman]

have you checked the water pump belt tensioner and the water pump itself ?...G.

[aircougar1]

Could be gear roll-over, or "chatter" as that part of the trans sits right under the filter assembly...??? But it should go away when you push in the clutch...