Brakes - Rattling/Buzzing Noise from IP Area

BULLETIN NO.: 95-T-31B

ISSUE DATE: March, 1997

GROUP/SEQ. NO.: Brakes - 07

CORPORATION NO.: 585005R

SUBJECT:
Buzzing, Rattling or Fluttering Noise Coming from Instrument Panel Area During Slow Speed Operation (Replace Power Brake Booster Check Valve Assembly)

Due to an addition of a color to help identify a part in step 6b and an error explaining which bulletin to discard, this bulletin is being revised and supercedes bulletin 95-T-31A, which should be discarded.

MODELS AFFECTED:
1995 Saturns built before and including VIN SZ371429

CONDITION:
Some customers may comment about a buzzing, rattling or fluttering noise coming from the instrument panel area during slow speed vehicle operation.

CAUSE:
These noises may be caused by the power brake booster check valve assembly and can be significantly reduced by replacing with a new power brake booster check valve assembly.

CORRECTION:
To verify that the noises are caused by the power brake booster check valve assembly, refer to the procedures in this bulletin.

PROCEDURES

1. Turn all accessories (radio, HVAC blower motor, etc.) Off.

2. Make sure windows and sunroof (if equipped) are closed.

IMPORTANT:
The surrounding area where the verification procedure is being performed should be quiet, and the engine cooling fan must be Off.

3. Slowly accelerate the vehicle from a stopped position in "D" (automatic transaxle) or 1st gear (manual transaxle) to 1500 rpm.

4. Release the accelerator pedal and listen carefully for a buzzing, rattling or fluttering noise coming from the instrument panel area inside of the vehicle.

5. Perform steps 3 and 4 several times to verify where the noise is coming from.





6. If the noise is coming from the instrument panel area, check the power brake booster check valve assembly to verify it is black in color.

a. If it is black in color, remove the power brake booster check valve and grommet from brake booster and proceed to step 7.

b. If it is brown or gray in color, further diagnosis of the vehicle will be required to determine the cause of the buzzing, rattling or fluttering noise, using the Chassis Ear Tool (SA9217NE) or equivalent.

7. Remove power brake booster check valve from vacuum hose.

8. Lubricate new grommet with silicone grease and install in brake booster.

IMPORTANT:
The new power brake booster check valve (P/N 21012702) is brown or gray in color and includes a new grommet.

9. Lubricate the power brake booster check valve with silicone grease and install into vacuum hose.

10. Install power brake booster check valve into grommet installed in brake booster.

11. Perform steps 3 through 5 to verify that the noise condition has been repaired.





PARTS REQUIREMENTS

CLAIM INFORMATION:

To receive credit for this repair during the warranty coverage period, submit a claim through the Saturn Dealer System using the appropriate Electronic Labor Time Guide and Labor Operation Code H1240.





DISCLAIMER