Well it seems im having a recurring problem, i have an 87 305TPI Trans Am with a 700r4, stocke everything except NGK v power plugs, and taylor wires, also an intake, with a MAF in the stock location. I have recently replaced my alternator with a Refurbished one from Rockauto, and also replaced the alternator belt. My problem is i have a loud squeal coming from what sounds like the alternator. My old alternator was bad, i could hear the bearing when i could turn it by hand, only problem is that it has been replaced with a new one. The sound also seems to be related to the transmission, as it stops when the car shifts into second. If im at WOT with the pedal to the floor i will get the squeal alll the way through first no matter what the RPMs. This sound goes away when the car is warm though, and wont occur after more then ten mins of driving. Previously before i replaced my alternator, the squeal would not go away even after the car was warm. My other problem is a rough idle, when cold the car will not idle, but when warm it will idle perfectly. I recently replaced and reset the TPS also. So, any ideas? the sound defiantly sounds like its coming from the front passenger side of the engine. Could it be my smog pump? im not really sure what to make of how it only happens in 1st gear. I hope its not my transmission or anything but i know little about transmissions. Thanks chris

Serpentine Belt? If so then probably tensioner pulley or waterpump pulley bearings are going. If not serpentine likely a belt slipping.

You can use a rubber tube with a funnel as a stethoscope.

Make sure you stay away from moving parts.

Aim the funnel at various areas till you find the source.

◙◙◙◙◙◙◙◙◙◙◙◙◙◙◙
Happy Racing!

Its your belt. I had that happen on my 87 IROC a few months back when I replaced the alternator. I didn't tighten the belt enough that it caused it to squeal. It would squeal at startup and after a few minutes it goes away. I then tighetened it and the problem has disappeared.

I have a v-belt setup on this car, i have the alternator as tight as i can get the belt, and i have applied belt lubricant to the belt. How tight would i need to have the alternator belt to get it to stop squealing, since there is no tensioner....

Belt lubricant never helped me with any of my cars. Chances are by now the belt is glazed from the heat generated and won't grip no matter how tight it gets, I'd recommend getting a new one. When you go to tighten the alternator bolts use a breaker bar or large wrench (>18") as leverage to pull the alternator outward to tighten the belt. You might be able to tighten down the bolts if you can pull with one hand, otherwise get someone to help you. Always worked fine for me.