GM Service Manual Online
For 1990-2009 cars only

Intake Manifold Inspection/Replacement After Severe Internal Engine Damage

Subject:Intake Manifold Inspection/Replacement After Severe Internal Engine Damage

Models:2008 and Prior Passenger Cars and Trucks (Including Saturn)
2008 and Prior HUMMER H2, H3
2008 and Prior Saab 9-7X



This bulletin is being revised to include additional models and model years. Please discard Corporate Bulletin Number 00-06-01-026A (Section 06 - Engine).


When replacing an engine due to internal damage, extreme care should be taken when transferring the intake manifold to the new Goodwrench service engine long block. Internal damage may result in the potential discharge of internal engine component debris in the intake manifold via bent, broken, or missing intake valves. After removing the intake manifold from the engine, the technician should carefully inspect all of the cylinder head intake ports to see if the valve heads are still present and not bent. Usually when the valve heads are missing or sufficiently bent, internal engine component debris will be present to varying degrees in the intake port of the cylinder head. If this debris is present in any of the cylinder head intake ports, the intake manifold should be replaced. This replacement is required due to the complex inlet runner and plenum configuration of most of the intake manifolds, making thorough and complete component cleaning difficult and nearly impossible to verify complete removal of debris. Re-installation of an intake manifold removed from an engine with deposits of internal engine component debris may result in the ingestion of any remaining debris into the new Goodwrench service engine. This may cause damage or potential failure of the new service engine.