Twin-Turbo Sequential Valve Control Malfunction
2019-2024 BMW 3 Series G20 2.0L I4 Turbo B48
Description
The sequential turbo control valve that manages the transition between the small and large turbo in a sequential twin-turbo system is malfunctioning.
Symptoms
- Check Engine Light
- Power drop at mid-RPM during turbo transition
- Turbo lag spike at switchover point
- Hesitation during acceleration
- Boost pressure oscillation
- Exhaust note changes abruptly
Common Causes
- Sequential valve actuator failure
- Valve stuck partially open or closed
- Vacuum/pressure line to valve disconnected
- Control solenoid electrical fault
- Carbon buildup on valve
Diagnostic Steps
- Monitor boost pressure during turbo transition RPM range
- Command sequential valve via scan tool
- Check vacuum supply to valve actuator
- Test control solenoid resistance
- Inspect valve for carbon deposits
Repair Notes
Replace sequential turbo control valve or actuator. Clean carbon deposits from valve seat. Verify smooth turbo transition after repair.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0011Intake Camshaft Position Timing Over-Advanced Bank 1
- P0012Intake Camshaft Position Timing Over-Retarded Bank 1
- P0013Exhaust Camshaft Position Actuator Circuit/Open Bank 1
- P0014Exhaust Camshaft Position Timing Over-Advanced Bank 1
- P0015Exhaust Camshaft Position Timing Over-Retarded Bank 1
P3030 on Other Vehicles
Common Questions
What does code P3030 mean on a 2019-2024 BMW 3 Series G20?
P3030 stands for "Twin-Turbo Sequential Valve Control Malfunction". The sequential turbo control valve that manages the transition between the small and large turbo in a sequential twin-turbo system is malfunctioning.
What are the symptoms of P3030 on a BMW 3 Series G20?
Common symptoms of P3030 include: Check Engine Light, Power drop at mid-RPM during turbo transition, Turbo lag spike at switchover point, Hesitation during acceleration, Boost pressure oscillation, Exhaust note changes abruptly.
What causes P3030 on a 2019-2024 BMW 3 Series G20?
Common causes of P3030 include: Sequential valve actuator failure, Valve stuck partially open or closed, Vacuum/pressure line to valve disconnected, Control solenoid electrical fault, Carbon buildup on valve.