Pontiac - Grandprix :: Car Sounding Like There Is Metal In The Pistons And Belts Jumping Off

So the other day I was driving the car and it was working fine, shut it off and turned it on like 4-5 times that day as I was driving around, then I went to check the muffler and when I started it it sounded like someone jammed a bunch of metal shavings in the engine. The engine is completely fine and there is nothing in it I know that for a fact, and the fact that the belt keeps jumping off is a def pointer that its something to do with a pulley. My friend thinks its the tensioner pulley because its jumping like crazy when the engine is running but the sound is horrid.

'm gonna have a friend come look at it tomorrow after work. Also, my friend snapped the bottom bolt on the power steering pump and i left the broken piece in and I always heard it rattling and it was bent when I checked cuz I thought that's what was making the sound. So that popped out enough to hit the pulley and bend what was left of the bolt down. I spun each pulley and I didn't hear any sounds, and I tried to shake them and none felt loose. Its got 130k on it but still, 1 problem after another after another. Could that broken bolt that came out and hit the pully possibly jarred it off balance or something? If the tensioner pulley isn't broken then something is making the belt stop because its pulling it down periodically. What I should look for to fix it.