Powertrain
Definition only
Lights the check engine lamp
P2CB8: Turbocharger/Supercharger Boost Pressure B Too High – Mechanical
Standardized SAE J2012 code · P2Cxx codes
What does P2CB8 mean?
The boost pressure on branch B exceeds the calibrated maximum. Mechanical fault — wastegate stuck closed or boost control valve jammed.
The code tells you which monitor failed, not which part is broken. Test before replacing parts.
Symptoms
- Check engine light on
- Significant power loss / limp mode
- Possible blue or black smoke from exhaust
- Whistling or hissing sound from intake
Common causes
- High Wastegate stuck closed
- Medium Boost control valve jammed
Likelihood is a general estimate across vehicles; your make and model may differ.
Add your car to see reports of P2CB8 on the same make and model first.
P2CB8 in the community
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