P226B
Turbocharger/Supercharger A Boost Pressure Too High - Mechanical
Boost pressure on turbo A exceeds the upper threshold and the cause is mechanical (wastegate stuck closed, VGT vanes stuck closed) rather than electrical drive fault.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: hard
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
Ordered by how often each turns out to be the cause.
- Wastegate or VGT stuck closedCommon
Parts involved
- Turbocharger
- Wastegate
P226B is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.