Fault-Code Library · Air metering
P2279: Intake air system leak
The ECU detects extra unmetered air entering the intake system.
Common symptoms
- •Rough idle
- •Hissing noise
- •Lean faults
- •Reduced power
Likely causes
- •Split intake hose
- •PCV failure
- •Loose clamp
- •Intake manifold or charge-pipe leak
First checks
- •Smoke-test the intake and PCV system
- •Inspect charge pipes and clamps
- •Compare fuel trims at idle and under load
Important
Unmetered air can create lean running, misfires, and misleading oxygen-sensor faults.
A fault code identifies a detected condition, not a failed part. Confirm manufacturer-specific subcodes and live data.
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