P3620high severityPowertrain
Cylinder Deactivation System Bank 1 Malfunction
on 2011 Chevrolet Express 6.0L V8 Vortec · RWD
What this code means
The cylinder deactivation system (Active Fuel Management/Multi-Displacement) for Bank 1 has detected a fault. The system deactivates cylinders during light load for fuel savings.
Symptoms
- Check Engine Light
- Engine vibration at highway cruise
- No cylinder deactivation occurring
- Reduced fuel economy
- Engine sounds different than normal
- MIL with misfire-like symptoms
Common causes
- Deactivation solenoid failure
- VLOM (valve lifter oil manifold) stuck
- Low oil pressure to lifters
- Collapsed deactivation lifter
- Oil passage blockage
Diagnostic steps
- Read cylinder deactivation status PIDs
- Command deactivation on/off with scan tool
- Check oil pressure at VLOM
- Test deactivation solenoid resistance
- Monitor individual cylinder contribution
Repair notes
Replace faulty deactivation solenoid or VLOM assembly. Collapsed lifters require cylinder head work. Use AFM-compatible oil and filter.
Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0011
Intake Camshaft Position Timing Over-Advanced Bank 1
P0012
Intake Camshaft Position Timing Over-Retarded Bank 1
P0013
Exhaust Camshaft Position Actuator Circuit/Open Bank 1
P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
Exhaust Camshaft Position Timing Over-Retarded Bank 1