I own a 2005 Nissan Sentra with a 1.8S 4 cyl. engine. It has 36,000 miles. I noticed when running the AC in the summer that it has a “chirp” during a hard acceleration when the automatic transmission shifts gears. Also, the last time it rained (I live in Phx. so it doesn’t rain often) that when I started the car, there was a squealing noise that lasted until the car warmed up. I thought it was the drive belt. I took the car to the dealer and they “tightened” the drive belt. Obviously it didn’t work or I wouldn’t be asking the question here. I still have a warranty on this car and I want to get it fixed before the warranty is up or something worse happens to the car. Could this be a pulley or a bearing going out on this car? By the way, I already replaced the head gasket (under warranty) that failed and was sucking oil into the #3 cylinder.
As far as I know (I may be wrong with your vehicle) the only thing that tightens the drive belt (Serpentine belt) is a tension pulley.
It’s possible the belt is glazed or cracked or the pulley bearing is worn.
The ‘chirping’ sound may also be from any of the pulleys. The belt should be removed and each pulley turned by hand.
IF a worn pulley bearing is found, use a straight edge and ensure all the pulleys are in alignment.