Engine and gearbox (P)
P0299: Turbocharger underboost condition
The engine control unit has detected that the boost pressure from the turbocharger is lower than the target value. This can affect engine performance and efficiency.
Checked by a licensed car technician · last reviewed 29 September 2026
Symptoms
- Reduced engine power
- Poor acceleration
- Increased fuel consumption
- Engine warning light on
Common causes
- Charge-air leak
- Weak actuator
- Turbocharger wear
- Faulty boost pressure sensor
How to check it yourself
- Inspect hoses and connections for leaks
- Pressure-test charge-air system
- Check actuator travel and boost control
- Inspect turbocharger for wear
Can I keep driving?
The car can still 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