VAG OBD Codes
the TSI & TDI faults explained
The codes that actually show up on VW, Audi, Škoda and Seat — turbo, intake flaps, timing and misfires — explained with causes and fixes.
Volkswagen / Audi (VAG) check engine light codes
Volkswagen Group (VAG) models use standard OBD-II engine codes plus a very detailed layer readable with VCDS or OBDeleven. The P-codes below are among the most reported across TSI petrol and TDI diesel engines.
If you own a VAG car and the check engine light is on, start here.
OBD-II code decoder
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Most common Volkswagen / Audi (VAG)
Classic VAG faults behind these codes.
| Code | Description |
|---|---|
| P0011 | "A" Camshaft Position Timing Over-Advanced (Bank 1) |
| P0171 | System Too Lean (Bank 1) |
| P0299 | Turbocharger Underboost Condition |
| P0300 | Random/Multiple Cylinder Misfire |
| P0401 | EGR Flow Insufficient |
| P0420 | Catalyst System Efficiency Below Threshold (Bank 1) |
| P0441 | EVAP System Incorrect Purge Flow |
| P2015 | Intake Manifold Runner Position Sensor Range |
Common Volkswagen / Audi (VAG) faults
Classic VAG faults behind these codes.
Turbo underboost (P0299) — boost leaks, wastegate wear, or vacuum hoses on TSI engines.
Intake manifold flaps (P2015) — carbon buildup on the runner actuator, common on direct-injection TSI.
Timing over-advanced (P0011) — oil pressure or VVT solenoid issues on 2.0 TSI.
Misfires (P0300) — coils and plugs, very common on 1.2/1.4 TSI.
EVAP purge (P0441) — purge valve faults across the range.
Volkswagen / Audi (VAG) FAQ
What causes P0299 on VW TSI engines?
Is P2015 a big repair?
Why do VW engines misfire?
Do I need VCDS to fix VAG codes?
Are P codes the same across Audi and VW?
Codes vary slightly by model, year and engine. Always confirm with a proper diagnosis. Manufacturer-specific codes (P1xxx/P2xxx) may differ from generic descriptions.
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Decode your Volkswagen / Audi (VAG) code now
Use the free decoder below, or browse the most common Volkswagen / Audi (VAG) codes.