99 olds 88 weird rattle

We have a 99 olds 88. just recently on start up it has a loud metallic rattle that sounds like its coming from the top of the engine. My alternator went out yesterday and we replaced it hoping that would take care of the noise but it didnt. Its just a very loud noise that sounds like metal clanging around. We know we have a bad CV joint on it due to popcorn sounding noise when turning right. But I dont think that could cause it at all. I was wondering if anyone else had this issue. Some days when you start it the noise is quiet and some days it is extrememly loud. Any idea anyone. We cant find this noise.

Just one more bit of information. To me it sounds like a starter that is free wheeling after start up but it is coming from the top of the engine.Thats the best way to describe it. I know its hard to diagnose a noise even when looking at the car but I just thought someone else might have had this problem.

The rattling noise ended up being the starter. Come to find out that cured another noise too. We had a popping noise when turning right. we thought we were gonna have to replace a cv joint. turns out it was the bendix being pulled toward the flywheel. Just thought id post the answer in case this helps anyone else out.