Hi all. I've started to notice a chirping noise (sounds like a quiet belt chirp) coming from the front of my car somewhere. It's strange though, and I am lost as to what it could be. I know it's almost impossible to trouble shoo a noise, without actually hearing it in person, but I'll give it a shot. Thenoise is only present when rolling between 15-30 MPH and on the brake. The noise only develops when pressing on the brake. I have had several people suggest that it could be the pads or something similar. This is definately not the case. The noise is there...as soon as you lightly touch the brake, or press down on the brake. Even just enough to make the brake lights come on is enough for the noise to appear. This makes me think it's an electrical issue somehow. Could it be something with how the ABS works? I know nothing about how the ABS works.

I just wanted some opinions, or any known cases like this before I talk it back to the dealer to have them look at it. The car has just barely turned 4 thousand miles, so pads, or rotors are not to blame.

 

There is a TSB out on this something to do with the pulleys being misaligned. Look back a week or two in the topics and you will find it. Do a search on crickets chirping under my hood.

 

New car, new brakes. Mine did that for a while when I got it. It went away until I changed the brakes again. The misaligned pulley chirp comes from an idler pulley on the alternator bracket. It happens at idle whether the car is moving or not. There is a service bullitin against it. Your problem sounds like what happens to new brakes and rotors. Like you said, sounds are better diagnose in person.

 

Thanks for posts guys. I appreciate it.

 

Been there - done that - posted the TSB! The belt-pulley-alternator bracket change out was supposedly on '98 through '00 with a VIN breakpoint somewhere in the middle of '00. I wouldn't doubt if the problem is on newer models.

Anywho, this problem was most noticable when you first start the car, idling, and idling at lights. Here it is again.

Accessory Drive Belt - Squeak/Chirp Noise

BULLETIN NUMBER: 00-06-01-008

DATE: March 2000

SUBJECT: Accessory Drive Belt Squeak/Chirp Noise (Install New Double Row Idler Pulley, Generator Bracket and Serpentine Belt)

MODELS:
1998-2000 Chevrolet Camaro
1998-2000 Pontiac Firebird
Built Prior to VIN Breakpoint Y2107225 with 5.7L V8 Engine (VIN G - RPO LS1)

CONDITION: Some customers may comment on a squeak/chirp noise coming from the accessory drive serpentine belt. The noise will be most noticeable at idle and low engine speeds.

CAUSE: The serpentine belt squeak/chirp noise may be caused by misalignment between the idler pulley and crankshaft pulley. A slight rocking motion of the idler pulley causes the misalignment, which results in noise.

CORRECTION: To correct this condition on vehicles built prior to the above VIN breakpoint, install the new generator bracket, double row idler pulley and serpentine belt following Service Manual procedures.

Important: The new generator bracket can be identified by the depth of the idler pulley mounting pilot. The pilot dimension (2) on the new generator bracket is 10 mm. Dimension (2) on the previous bracket was 8.3 mm.