Need help with some noises
 

Hey guys, I just started my 87 924S today after it sat for like 6 months, Once I got the batery juiced up it fired right up. Then I heard to noise that I have heard before but never had time to really look into it, So Im gonna ask you guys what you think it is. The first noise Sounds like a heat sheald rattle on a Cat, it only happens around 4,000 rpm and usualy on Decel. It sounds louder up front buy the engine then it does when lawing down buy the exhaust, I really hate the noise, Its a hight pitch rattle, ANY IDEAS??????

The second noise sound like a door creaking, This happens when the car is idealing and the noise speeds up when rpm increase but the noise gets quieter. I checked my belts none are loose, Could it be a pully??? something with the Timming Belt??? or maybe the altinator??? Any Ideas would be great.

Thanx alot guys I really would like to get these noises out.

The first sound kind of sounds like a deteriorating catalytic converter, or perhaps a mount on it or the exhaust has cracked or come loose?
I didn't know there was a heat shield on the cat of non-turbo cars.
Although, since it only happens at around 4000rpm on engine deceleration, it could be something else?

The second one could be an idler pulley or tensioner. But it could also be the alternator, power steering pump or ac compressor. Check it out with a stethoscope to be sure.

One of the forgotten heat shields is the one covering the passenger engine mount. Since it is small and light it's harmonic is at higher rpms/frequencies. I found this out after doing my engine mounts.

can I just remove It or would I be risking cooking the mount??

I dont have a cat on my car so thats not the problem