Powertrain
generic / SAE
P23A6
Exhaust Heat Exchanger Bypass Valve B Stuck Open
Bypass valve B is stuck in the open position - exhaust bypasses the heat exchanger continuously, slowing engine warm-up.
SystemPowertrain
Typegeneric / SAE
GroupP2
Range / number3 / A6
Possible causes
- Valve stuck open high
- Carbon or debris buildup preventing free movement low
- Component wear with age - mechanical play low
Inspection / repair
- Difficulty: medium
- DIY: shop recommended
- Estimated cost: 250–1200 €
- Estimated time: 1.5–4 h
- Component: exhaust bypass valve b
- MIL / check engine light
- emissions-relevant
Sources
References
sae:J2012