i have a 90 accord lx when i first turn it on it makes a very loud screeching sound and then after a minute or two it stops then i put it on gear hit the gas and the screeching sound comes back also when i have it in parked and turn the A/C on the screeching sound comes on again i was told the harmonic balancer is what's causing this loud screeching sound, i dont want to order a harmonic balancer replace it and then ending up being something else thats causing this loud annoying sound does anyone know the symptoms of a bad harmonic balancer?

 

Where I would start is check the accessory belt tension. Usually if the belt is loose it will slip and that is what you hear. The AC runs off the same belt and puts more load on the belt causing it to slip once again. Thats were I would start.

 

No, either the serpentine belts are loose or they're bad in a way.

 

^I agree with these gents. That sounds like a textbook description of a loose belt.