P2279 on Audi
Intake Air System Leak
P2279 on Audi vehicles indicates intake air system leak. Au7o has documented this code across 1 Audi model — most commonly on S8. This code means the engine computer detected an air leak in the intake system downstream of the mass airflow sensor (unmetered air entering the engine). Because this air is not measured, the engine may run lean, idle roughly, or behave inconsistently. The computer flags it when fuel trims or airflow readings indicate more air is reaching the cylinders than the sensor accounts for. It is usually not an immediate safety issue but can cause drivability problems, poor fuel economy, and other related lean codes. Typical repair costs on Audi range from $300 to $900, depending on the specific model and root cause.
Common Causes of P2279
- •Cracked or loose intake hose / air duct after the MAF
- •Vacuum leak (hoses, gaskets, PCV)
- •Loose or damaged intake manifold gasket
- •Faulty or dirty mass airflow sensor
- •Leaking throttle body gasket
- •Unseated or cracked intake boot clamp
- •Failed PCV valve or hose
P2279 on Audi by Model
Audi S8(1 issue)
- PCV / Oil Separator Failure and Excessive Crankcase Vacuum2013-2018
The crankcase ventilation system on the 4.0T uses an integrated oil separator / PCV (pressure control valve) located in the engine valley. The diaphragm-style pressure regulator fails over time, producing excessive crankcase vacuum. A classic confirmation is that the oil filler cap is hard to twist off at idle due to strong suction. Failure drives rough idle, random multi-cylinder misfires, increased oil consumption, whistling/hissing, and can pull oil past seals — worsening the carbon and oil-burning picture already common on this engine. It is frequently misdiagnosed as a turbo or injector problem.
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View P2279 across all makes →Frequently Asked Questions
What does P2279 mean on Audi?▼
P2279 stands for "Intake Air System Leak." This code means the engine computer detected an air leak in the intake system downstream of the mass airflow sensor (unmetered air entering the engine). Because this air is not measured, the engine may run lean, idle roughly, or behave inconsistently. The computer flags it when fuel trims or airflow readings indicate more air is reaching the cylinders than the sensor accounts for. It is usually not an immediate safety issue but can cause drivability problems, poor fuel economy, and other related lean codes. On Audi specifically, this code is documented across 1 model.
What causes P2279 on Audi vehicles?▼
Common causes on Audi: Cracked or loose intake hose / air duct after the MAF, Vacuum leak (hoses, gaskets, PCV), Loose or damaged intake manifold gasket, Faulty or dirty mass airflow sensor, Leaking throttle body gasket. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P2279 on a Audi?▼
Repair costs on Audi range from $300 to $900, depending on the specific model and root cause.
Which Audi models have P2279 documented?▼
Au7o has documented P2279 on 1 Audi model: S8.