Cylinder Deactivation (Active Fuel Management) System Diagnosis for Pontiac G8 2008

1. Check the engine oil level. Fill, as required.
2. Using the scan tool, inspect for diagnostic codes within the engine control module (ECM). Refer to Diagnostic System Check - Vehicle. Repair, as required.
3. Verify correct engine oil pressure and operation of the cylinder deactivation oil pressure relief valve. Refer to Oil Pressure Diagnosis and Testing and Cylinder Deactivation (Active Fuel Management) Oil Pressure Relief Valve Diagnosis and Testing.
4. Verify correct operation of the cylinder deactivation system components. Refer to Cylinder Deactivation (Active Fuel Management) System Compression Test.
5. Remove the valve lifter oil manifold (VLOM). Refer to Valve Lifter Oil Manifold Replacement.
6. Verify correct operation of the VLOM. Refer to Cylinder Deactivation (Active Fuel Management) Valve Lifter Oil Manifold Diagnosis and Testing.
7. Replace the cylinder deactivation valve lifters, as required. Both intake and exhaust lifters should be replaced in pairs. Refer to Valve Lifter Replacement.