Engine and gearbox (P)
P003A: Turbo Boost Control Position Limit Exceeded
The engine control module has detected that the turbocharger or supercharger boost control position has exceeded its learning limit. This affects the control of boost pressure.
Checked by a licensed car technician · last reviewed 30 September 2026
Symptoms
- Reduced engine power
- Poor acceleration
- Check engine light on
- Possible whistling noise from turbo
Common causes
- Wastegate actuator worn or sticking
- Linkage rod stretched or loose
- Faulty boost pressure sensor
- Vacuum leaks in the boost control system
How to check it yourself
- Inspect the wastegate actuator for wear or sticking
- Check the linkage rod for proper tension
- Test the boost pressure sensor for correct operation
- Inspect for vacuum leaks in the boost control system
Can I keep driving?
The car can be driven, but performance may be reduced.
General guidance, not a professional inspection. Confirm faults with measurements before buying parts, and use a qualified mechanic for brakes, steering, fuel leaks, airbags, and other safety-critical work. Terms and disclaimer