Cobalt L4-2.4L VIN B (2006)
The numbers below refer to the step numbers on the diagnostic table.
2. This test is to verify that the symptom is present during diagnosing. Other vehicle components may cause a similar symptom.
3. This test is to verify that the drive belt is causing the rumbling noise. A rumbling noise may be confused with an internal engine noise due to the
similarity in the description. Remove only one drive belt at a time if the vehicle has multiple drive belts. 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. Inspecting the drive belt is to ensure that the belt is not causing the noise. Small cracks across the ribs of the drive belt will not cause the noise.
Belt separation is identified by the plys of the belt separating and may be seen at the edge of the belt or felt as a lump in the belt.
5. Small amounts of pilling is a normal condition and is acceptable. When the pilling is severe, the drive belt does not have a smooth surface for
proper operation.
Drive Belt Squeal Diagnosis
Drive Belt Squeal Diagnosis
Diagnostic Aids
A loose or improper installation of a body component, a suspension component, or other items of the vehicle may cause the squeal noise.
If the noise is intermittent, verify the accessory drive components by varying the loads, making sure the components are operated to maximum
capacity. An overcharged A/C system, power steering system with a pinched hose or wrong fluid, or a generator failing are suggested items to inspect.
Test Description
