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. | |||||||||||||
Plugged oil filter | Replace the oil filter. | ||||||||||||
Low oil pressure |
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Loose and/or worn valve rocker arm attachments |
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Worn valve rocker arm | Replace the valve rocker arm. | ||||||||||||
Bent or damaged push rod | Inspect the following components, and replace as required:
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Improper lubrication to the valve rocker arms | Inspect the following components, and repair or replace as required:
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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 engine camshaft lobes |
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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 stick) | Inspect the following components, and repair as required:
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