Powertrain
generic / SAE
P23AA
Turbocharger Bypass Valve A Stuck
The turbocharger bypass valve A (compressor bypass for surge protection or wastegate-style boost relief) is mechanically stuck. Boost control is impaired - either no relief on overspeed or no boost build-up depending on which position the valve is stuck in.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number3 / AA
Possible causes
- Valve stuck due to debris or actuator failure high
Symptoms
- Check engine light on
- Significant power loss / limp mode
- Possible blue or black smoke from exhaust
- Whistling or hissing sound from intake
Inspection / repair
- Difficulty: medium
- DIY: shop recommended
- Estimated cost: 200–1500 €
- Estimated time: 1.5–5 h
- Component: turbo bypass valve a
- MIL / check engine light
- emissions-relevant
Sources
References
sae:J2012