This fell off my jeep!

Help!

I have a 2009 Jeep Patriot and while I was driving home today this piece fell off and scared the living shizzle out of me. It made such a loud noise! For the past few weeks my Jeep's lights have been flickering and she kept feeling like she was going to shut off. Now that this piece popped off she seems fine. It must have been loose and now I am looking for an answer on where this piece came from and what it does.

Can anyone tell me what this piece is and where it came from under my hood?

Also, can i screw it back on or do I have to fully replace it?

Thanks,
Anna

Help!

I have a 2009 Jeep Patriot and while I was driving home today this piece fell off and scared the living shizzle out of me. It made such a loud noise! For the past few weeks my Jeep's lights have been flickering and she kept feeling like she was going to shut off. Now that this piece popped off she seems fine. It must have been loose and now I am looking for an answer on where this piece came from and what it does.

Can anyone tell me what this piece is and where it came from under my hood?

Also, can i screw it back on or do I have to fully replace it?

Thanks,
Anna
It's a pulley for a belt on the car. Use a trouble light and look on the front of the motor. It may be an idler pulley.
Any it needs repaired or replaced or you will have problems.