Loud Noise from AC while Idling or at low speed

nissan
maxima

#1

Nissan Maxima 1994 about 160 K Miles. Runs fine without AC. When AC is on and the car idles at stop light, etc. or the speed is below 15 miles for long time, I hear real loud some what high pitched noise from the engine towards the passenger side. Noise goes away as soon as I start driving. Noise stops after a few seconds while idling and comes back again if I am at a stop light for a long period. I have not tried accelarating the car while idling. Any suggestions?


#2

I would suspect the A/C compressor’s clutch as being the source of the noise.


#3

A loose AC compressor drive belt is another possibility.


#4

How old is the serpentine belt? An old dried out belt can cause all sorts of unpleasant noises. If it’s more than 4 or 5 years old replace it.

Ed B.


#5

The pattern of occurring only at very low speed or idle is unusual. It does not seem to fit with any of the usual suspects.

One noise item that has not yet been mentioned is the bearing in the serpentine belt tensioner. That would be my first suspect.


#6

That is another good possibility.


#7

Well, there’s almost no question at all that the issue is in with the serpentine belt system - whether an old belt, bad pulley etc.

vijay_a are you at all handy with tools? Its normally pretty easy to pull a belt, check it & check some pulleys.


#8

I will though one additional possibility into the soup: How about a vacuum problem - blend door controls?