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[Tom]

Has anyone experienced a fairly loud chirping noise problem on a 2002
LeSabre? the noise is intermittent - stops when brakes are applied - or
when I activate the recirculate button on the AC - the AC or heat must
be on. I can pinpoint the noise as "in the vicinity" of the alternator.
Only occurs after highway travel exceeding 50-70 miles and can last for
about five minutes before it stops. Noise changes pitch somewhat as
engine revs increase or decrease. Not the rotors or pads as the noise
continues when stopped and engine idling. So far two Buick dealers are
clueless. The alternator and serpentine belt have been replaced with no
effect.

[Wendy & John]

"Tom" wrote:

Has anyone experienced a fairly loud chirping noise problem on a 2002
LeSabre? the noise is intermittent - stops when brakes are applied - or
when I activate the recirculate button on the AC - the AC or heat must
be on. I can pinpoint the noise as "in the vicinity" of the alternator.
Only occurs after highway travel exceeding 50-70 miles and can last for
about five minutes before it stops. Noise changes pitch somewhat as
engine revs increase or decrease. Not the rotors or pads as the noise
continues when stopped and engine idling. So far two Buick dealers are
clueless. The alternator and serpentine belt have been replaced with no
effect.
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We had a similar elusive chirp condition in our 92 Buick 350TBI. Suspected
the alternator because electric loads affected chirp; suspected the AC
compressor clutch pulley; suspected and replaced idler pulley and belt.
No one could find the cause, which continued for about 400 miles before
the problem showed itself: Sparks started flying from the water pump
bearing, followed by a spray of bearing rollers.

New water pump: Blessed silence.

Wendy & John.
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