GM Service Manual Online
For 1990-2009 cars only

Cause

Correction

Worn, damaged or loose rocker arm

    • Inspect the valve rocker arms.
    • Repair or replace damaged components as required.

Worn, damaged, loose or bent valve push rod

    • Inspect the valve push rods.
    • Repair or replace damaged components as required.

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

    • Inspect the valves.
    • Inspect the valve guides.
    • Repair or replace damaged components as required.

Worn, damaged or dirty valve lifter

    • Inspect the valve lifters.
    • Inspect the camshaft.
    • Repair or replace damaged components as required.

Worn or damaged camshaft lobe

    • Inspect the camshaft.
    • Inspect the valve lifters.
    • Repair or replace damaged components as required.

Worn, damaged or loose timing chain and sprockets

    • Inspect the timing chain and sprockets.
    • Repair or replace damaged components as required.