P2279 — Intake Air System Leak Bank 1

P2279: Intake Air System Leak Bank 1 — what it means, the affected system and what to check before replacing parts.

Meaning, symptoms, causes and checks

Intake Air System Leak Bank 1. Basic catalogue definition; diagnostic details have not yet been reviewed.

Affected system: Powertrain

Symptoms

  • A check-engine warning may accompany an intake-air leak.
  • Idle may become uneven, and the engine may hesitate or stall.
  • Hissing or whistling near the intake is possible; a brake-assist complaint needs immediate separate attention.

Possible causes

  • Loose or split intake tubing, clamps or vacuum hoses that let in unmetered air.
  • A leaking intake-manifold gasket or throttle-body seal.
  • Leaks in the crankcase ventilation system or in connected vacuum lines.

What to check

  • Confirm P2279 and related air-metering or mixture codes.
  • Visually inspect the intake ducting, hose connections, PCV lines and gaskets for leaks.
  • Listen for intake hissing without approaching moving or hot parts.
  • If visual checks are inconclusive, use an appropriate intake smoke test to locate unmetered-air paths.

Also written as: P2279-00, P227900 (some scan tools add the fault-type byte, e.g. -00).