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Cylinder Deactivation (Active Fuel Management) System Diagnosis

Engine Mechanical - 5.3L L84 or 6.2L L87 | Diagnostic Information and Procedures | Document ID: 5601113 Cylinder Deactivation (Active Fuel Management) System Diagnosis

  1. Measure the engine oil level. Fill, as required. Approximate Fluid Capacities
  2. Inspect for diagnostic codes within the engine control module (ECM). Diagnostic System Check - Vehicle Repair, as required.
  3. Verify proper engine oil pressure, and proper operation of oil pump oil control solenoid valve {if equipped} and oil pump pressure relief valve. Oil Pressure Diagnosis and Testing
  4. Verify proper operation of the active fuel management system components.
  5. Replace the valve lifter oil solenoid valves, as required.
  6. Replace the active fuel management valve lifters, as required. Both intake and exhaust lifters should be replaced in pairs. Valve Lifter Replacement - Left Side Valve Lifter Replacement - Right Side