Cobalt L4-2.0L SC VIN P (2005)
may not be operating and the engine may overheat. Also DTCs may set when the engine is operating with the drive belt removed.
4. The drive belt may cause a vibration. While the drive belt is removed this is the best time to inspect the condition of the belt.
6. Inspecting of the fasteners can eliminate the possibility that a wrong bolt, nut, spacer, or washer was installed.
8. This step should only be performed if the fan is driven by the drive belt. Inspect the engine cooling fan for bent, twisted, loose, or cracked blades.
Inspect the fan clutch for smoothness, ease of turning. Inspect for a bent fan shaft or bent mounting flange.
9. This step should only be performed if the water pump is driven by the drive belt. Inspect the water pump shaft for being bent. Also inspect the
water pump bearings for smoothness and excessive play. Compare the water pump with a known good water pump.
10. Accessory drive component brackets that are bent, cracked, or loose may put extra strain on that accessory component causing it to vibrate.
Drive Belt Whine
Drive Belt Whine Diagnosis
Diagnostic Aids
The drive belt will not cause the whine noise.
If the whine noise is intermittent, verify the accessory drive components by varying their loads making sure they are operated to their maximum
capacity. Such items but not limited to may be an A/C system overcharged, the power steering system restricted or the wrong fluid, or the generator
failing.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
3. This test is to verify that the noise is being caused by the drive belt or the accessory drive components. When removing the drive belt the water
pump may not be operating and the engine may overheat. Also DTCs may set when the engine is operating with the drive belt removed.
4. The inspection should include checking 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
inspection and replacement procedure.
