P226B code meaning
Turbocharger/Supercharger A Boost Pressure Too High - Mechanical
Powertrain system Generic code P22xx codes Check engine light
What P226B means
P226B reports boost from turbocharger or supercharger A rising too high for a mechanical reason, for instance a wastegate or bypass that will not open or a seized actuator linkage, rather than a sensor or wiring fault. VW's 2014 book for the supercharged Touareg 3.0 TSI sets it when boost passes 250 kPa. GM uses the code only for European calibrations: its 2018 diesel tables list P226B as an EOBD code in the boost-system fault groups, while the US software maps the same fault group to P2263. CARB requires boosted engines to detect overboost. Where P0234 judges a deviation above the target, P226B points to a mechanical cause; P2262 describes boost that does not appear at all. To protect the engine the ECM usually reduces torque, and some engines open a relief path.
P226B at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyHard
- Typical labor1 to 6 hours
- Clears after repairAfter a drive cycle
Symptoms of P226B
- Sudden power cut or reduced-power mode under load
- MIL on
- Unusually strong surge of power just before the cut
Common causes of P226B
- Most likelyWastegate flap seized closed by corrosion or carbon
- PossibleSeized or misadjusted wastegate or VGT actuator linkage
- PossibleVacuum or pressure line to a pneumatic actuator leaking or blocked
- Less likelySupercharger bypass valve not opening
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
TurbochargerWastegateWastegate actuator
What each part of P226B means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 2 | Area: fuel and air metering (injector circuit). |
| 6B | The exact fault in that area. |
What to do next
- Note P226B and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P226B
What does P226B mean?
P226B means "Turbocharger/Supercharger A Boost Pressure Too High - Mechanical". P226B reports boost from turbocharger or supercharger A rising too high for a mechanical reason, for instance a wastegate or bypass that will not open or a seized actuator linkage, rather than a sensor or wiring fault. It is a generic code, so it means the same on every make.
Is it safe to drive with P226B?
Drive gently and only to a workshop. With P226B the car can go into limp mode (reduced power) to protect itself.
Will P226B fail an emissions test?
Yes, it can. P226B is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P226B to fix?
Difficulty: hard. A typical repair takes 1 to 6 hours of work. This is a job for a workshop.
Will P226B clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.