P056F
Cold Start Turbocharger/Supercharger Boost Control B Performance
Generic OBD-II
Common symptoms
What you'll notice
- Check for any vacuum leaks in the intake system and repair them if necessary
- Inspect the turbocharger/supercharger bypass valve and replace if faulty
- Perform a thorough cleaning of the intake system and throttle body
- Test and replace the wastegate solenoid if it is not functioning properly
- Check the sensor readings of the boost pressure sensor and replace if readings are inaccurate
Common causes
Most likely first
- Faulty turbocharger or supercharger
- Boost pressure sensor malfunction
- Wastegate valve stuck open
- Boost pressure control solenoid failure
- Clogged air intake or intercooler
How to diagnose & fix
Work through it in order
- Lack of power during acceleration
- Engine misfire or hesitation
- Decreased fuel efficiency
- Rough idle or stalling
- Check engine light illuminated
Read & clear P056F yourself
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