Upper Engine Noise, Regardless of Engine Speed
WARNING: This page is about a different car, the 2005 Buick LaCrosse and 2005 Buick Allure. However, it is still accessible from the selected car via links, so may be relevant.
Upper Engine Noise, Regardless of Engine Speed
| Cause | Correction |
|---|---|
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IMPORTANT:
A cold piston knock which disappears in 1.5 minutes should be considered acceptable. A cold engine knock usually disappears when the specific cylinder's secondary ignition circuit is grounded out during diagnosis.
A light rattle/tapping noise may indicate a valve train, upper engine concern. |
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| Low oil pressure |
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| Loose and/or worn valve rocker arm attachments |
|
| Worn valve rocker arm | Replace the valve rocker arm. |
| Bent or damaged push rod | Inspect the following components, and replace as required:
|
| Improper lubrication to the valve rocker arms | Inspect the following components, and repair or replace as required:
|
| Broken valve spring | Replace the valve spring. |
| Worn and/or damaged valve rotators | Replace the valve rotators as required. |
| Worn or dirty valve lifters | Replace the valve lifters. |
| Stretched or broken timing chain and/or damaged sprocket teeth | Replace the timing chain and sprockets. |
| Worn timing chain tensioner, if applicable | Replace the timing chain tensioners as required. |
| Worn engine camshaft lobes |
|
| Damaged, broken, or dirty, balance shaft sprocket teeth, if applicable | Inspect the following components, and repair as required:
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| Worn valve guides or valve stems | Inspect the following components, and repair as required:
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| Stuck Valves Carbon on the valve stem or valve seat may cause the valve to stay open |
Inspect the following components, and repair as required:
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