Cause  | Correction  | ||||
|---|---|---|---|---|---|
Low oil pressure  | 
 
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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  | Set or replace the timing chain and sprockets.  | ||||
Worn or improperly set timing chain tensioner, if applicable  | Replace the timing chain tensioners as required.  | ||||
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 stay open.  | Inspect the following components, and repair as required: 
 
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