Test Description
WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The number(s) below refer to the step(s) in the diagnostic table.
- 3: This test is to verify that the whine is being caused by the accessory drive component(s). Remove the drive belt (s) and operate the engine for a few seconds, this will verify if the whining noise is related to the accessory drive component. With the drive belt(s) removed the water pump will not operate and the engine may overheat. Also diagnostic trouble codes (DTCs) may set when the engine is operate with the drive belt(s) removed.
- 4: The inspection should include checking the drive belt tensioner and the drive belt idler pulley bearings. The drive belt(s) may have to be installed and the accessory drive components operated separately by varying their loads. Refer to the suspected accessory drive component for the proper removal and installation procedure.
Drive Belt Whine Diagnosis
| Step | Action | Yes | No |
|---|---|---|---|
|
NOTE:
Refer to Belt Dressing Notice
in Cautions and Notices. DEFINITION: A high pitched continuous noise that may be caused by an accessory drive component failed bearing. |
|||
| 1 | Did you review the Symptoms - Engine Mechanical diagnostic information and perform the necessary inspections? | Go to Step 2 | Go to Symptoms - Engine Mechanical |
| 2 | Verify that there is a whining noise. Does the engine make the whining noise? |
Go to Step 3 | Go to Diagnostic Aids |
| 3 |
|
Go to Engine Noise on Start-Up, but Only Lasting a Few Seconds | Go to Step 4 |
| 4 |
|
Go to Step 5 | - |
| 5 |
|
- | System OK |