Turbocharger/Supercharger B Overboost Condition
Boost pressure on the secondary turbocharger/supercharger (B) on a sequential or twin-charged setup is above the upper threshold. Wastegate stuck closed, VGT vanes stuck, or boost pressure sensor reads high.
Affected components
- Turbocharger b
- Wastegate b
- Boost pressure sensor b
Common causes
- High likelihood: Wastegate stuck closed
- Medium likelihood: VGT vanes stuck closed
Possible symptoms
- Check engine light on
- Significant power loss / limp mode
- Possible blue or black smoke from exhaust
- Whistling or hissing sound from intake
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
- Reduced-power or limp mode may occur
Sources
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.