GM Service Manual Online
For 1990-2009 cars only

Cause

Correction

Worn, damaged or loose rocker arm

    â€¢ Inspect the valve rocker arms.
    â€¢ Repair or replace damaged components as required.

Worn, damaged, loose or bent valve push rod

    â€¢ Inspect the valve push rods.
    â€¢ Repair or replace damaged components as required.

Worn, damaged or stuck valve, carbon on the valve stem or valve seat

    â€¢ Inspect the valves.
    â€¢ Inspect the valve guides.
    â€¢ Repair or replace damaged components as required.

Worn, damaged or dirty valve lifter

    â€¢ Inspect the valve lifters.
    â€¢ Inspect the camshaft.
    â€¢ Repair or replace damaged components as required.

Worn or damaged camshaft lobe

    â€¢ Inspect the camshaft.
    â€¢ Inspect the valve lifters.
    â€¢ Repair or replace damaged components as required.

Worn, damaged or loose timing chain and sprockets

    â€¢ Inspect the timing chain and sprockets.
    â€¢ Repair or replace damaged components as required.