2001 Pontiac Sunfire SE 4 Cyl 2.20L
Loose Marbles/Rattling near Alternator & Serpentine Belt
Yesterday, I went to the store and everything was fine. When I came back out and started the car, it started making a rattling noise similar to dragging tin cans across pavement. It does this as soon as I start the engine and continues until I turn it off. It's roughly the same when idling, and driving at a consistent speed, but it does seem to be more intense when accelerating. The noise is LOUD. I've looked under the hood while the engine was running and I'm about 95% sure the noise is coming from the area around the alternator, serpentine belt, and coolant reservoir.
Several possibilities; worn alternator bearing, worn idler pulley bearing,belt tensioner is worn / faulty.