I believe that your alternator may need to be bench tested - when your a/c comperssor turns on (when your a/c turns on) this is a larger draw of required volts for your car, and therefore a larger load on your alternator. I believe that an alternator "struggling" to keep up with "demand" can cause the alternator belt to squeak. It could also be something as simple as a belt slippage - there is extra tension on the belt when another accessory is being used (your a/c). Check the condition of your belt. Think of paint finishes for a moment. If your belt has any "shiny" or "glossy" (called glazed) appearance, or has any cracks in it, then simply erplacing your belt could solve this. But if your belt is in good shape (has a dull or "matte" appearance), then have your alternator bench tested at a reputable auto parts store/mechanic. Another test you could do on your own is to start your car, then while it is running, disconnect the positive lead from your battery. If your alternator is running well, it should easily run your car on it's own w/out the battery. If your car stops running after disconnecting your battery, then your alternator is absolutely the culprit, and needs to be replaced. I am not a mechanic, but these are a few simple checks you can try yourself - good luck!Belt or A/C clutchTwo other possibilities:
1. Most likely -- The belt is wearing out, getting loose, etc. Check the belt for glazing (makes it look shiny). Check also the strength of the belt tensioner.. (Take the key out of the car for this check!!) If you can pull the belt more than an inch toward you, the belt and / or tensioner may be bad.
2. The A/C compressor clutch is wearing out. This is not as likely. This would have to be repaired by a professional.
replace alternator belt
if it was like my 99, then a belt was worn out, and will cause a chirping noise, if it is in the engine compartment, it is very likely to be a belt
If the chirping noise speeds up as the truck speeds up, check the u-joints in the drive line.
I need to know more, what model, what engine? It could be a belt, could be a pulley, could be a cam synchronizer.
A Cricket Or a Cicada makes a chirping noise.
When Exhaust brake is on squeak noise comes from the engine?"
Noise coming from engine in Oldsmobile Cutlass could be as a result of an oil leak in the rear of your engine. This makes the gears to wear off leading to severe knocking noise.
If your 2002 Ford Sport Trac is making a chirping noise when you do a cold start up, this could mean that you have a problem with the engine. You should have it looked at by a mechanic.
The noise is birds chirping.
Some toads and frogs do make a chirping like noise. It is the males that make this sound when they are scared or calling for a mate.
The noise on your house roof chirping at night is most likely birds. It could also be tree frogs if you have trees close to your roof.
I had the same chirping noise. My chriping was the belt and/or the power steering pump. I replaced both. no noise now. I would first replace the belt, then the pump
he he he
it´s possible that a bad hydraulic lifter is working dry.
they usually squeal really loud or they do a chirping noise.(chirping noise is very rare. my guinea pig only did it once. that was when she first met my dog)
you have a stuck valve
where is the humming noise coming from? if it's coming thru the speakers and matches the rev tone of the engine, then you have a bad ground in your stereo.
engine noise coming thru the radio is caused by a bad ground somewhere so instead of chasing that you go to a car stereo shop and buy a noise filter that hooks up to the ground wire coming off the radio.
whistling noise from engine will be caused by a leaky gasket,sucking air. this is usually the intake manifold gasket
your car is broken
Bearing noise is usually deeper and comes from farther down in the engine. Lifter noise is more of a ticking and is up in the engine heads.
A chirping whistling noise!