95 E 300D makes screetching sound when cold... any thoughts?
 

Greetings! My car (95 w OM 606 motor, non turbo) seems to screetch (not quite like a belt slipping, more like a metallic screechy vibration if that makes any sense, ) for the first few minutes when it is started. This began with the cold weather here in New England and seems to be getting louder. It is definitely coming from the front of the engine / fan area. If you rev the car above idle when cold, it also goes away. When it drops back to idle RPM it starts making the sound again, until warm. Could this be a water pump or fan clutch or something like that? Other than this, its running just fine. Thanks!