This concerns a 2001 Chevrolet Prizm (essentially the same thing as a
2001 Toyota Corolla).An intermittent, high-pitched squeak/squeal is coming from the left-hand side of the engine compartment, where the drive belt (aka "fan belt" or "serpentine belt") is located. This seemed to have suddenly started after the vehicle hadn't been driven for a month. It's also possible that it was happening before but I just didn't notice it. The noise goes away when accelerating and comes back (sometimes) when decelerating or maintaining a steady speed. Also, initially the squeal was heard quite frequently. However, I have taken this Prizm on several short test drives since I first noticed the noise, and the intermittent squealing seems to be getting less and less frequent with each test drive. It's almost as if the short test drives are helping to loosen something up, though that's just a guess.
Anybody have an idea about what could be causing the squealing noise? A friend suggested that it might be due to a loose belt, but I doubt that. I'd expect a squealing belt to get noisier during acceleration, not quieter.
Okay, I need to add a few things because the picture changed a little during my most recent test drive (made after I started writing this). The squealing doesn't always go away during acceleration. But it does seem to occur less frequently during acceleration. And I should also mention that sometimes the squeal has a definite rhythm to it when the engine is idling. At one point it sounded something like this: squeak-squeak-SQUEAK (pause), squeak-squeak-SQUEAK (pause), squeak-squeak-SQUEAK (pause)... In other words, two short squeaks followed by a longer and louder one.
Phil