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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2005 🢒 Chevy MD Steel Tilt (W Model) 🢒 Vehicle Control Systems 🢒 Vehicle DTC Information 🢒 Drive Belt Whine Diagnosis

Diagnostic Aids

The drive belt does not cause the whine. If the whine is intermittent, verify that it is not the accessory drive component by varying the loads. Ensure they are operating to their maximum capacity. An overcharged air conditioning (A/C) system, a power steering system restriction, incorrect fluid or a failing generator are suggested items to inspect.

Test Description

The numbers below refer to the steps in the diagnostic table.

  1. This step verifies that the whine is caused by the accessory drive component. Remove the drive belt and operate the engine for a few seconds. This verifies that the whining noise is related to the accessory drive component. With the drive belt removed, the water pump does not operate and the engine may overheat. Diagnostic trouble codes (DTCs) may set when the engine is operated with the drive belt removed.

    2.

  2. This step should include inspection of the drive belt tensioner and the drive belt idler pulley bearings. The drive belt 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.

Step

Action

Yes

No

Notice: Refer to Belt Dressing Notice in the Preface section.

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 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

  1. Remove the drive belt. Refer to Drive Belt Replacement - Accessory or Drive Belt Replacement - Air Conditioning.
  2. Operate the engine for no longer than 30-40 seconds.

Does the whining noise still exist?

Go to Engine Noise on Start-Up, but Only Lasting a Few Seconds

Go to Step 4

4

  1. Inspect for a failed accessory drive component bearing.
  2. Install the drive belt. Refer to Drive Belt Replacement - Accessory or Drive Belt Replacement - Air Conditioning.

Did you find and correct the condition?

Go to Step 5

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5
  1. Clear any codes.
  2. Run the engine in order to verify the repair.

Does the whining still exist?

--

System OK