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2012 TOYOTA 4RUNNER

4.0L V64WDAUTOMATICgas
8 active safety recalls on this vehicle — view recalls
Repairs0Labor595Torque3772Fluid9DTC921Battery1Maintenance0Recalls8
P2440moderate severityPowertrain

Secondary Air Injection System Switching Valve Stuck Open Bank 1

on 2012 Toyota 4Runner 4.0L V6 · 4WD

What this code means

The secondary air injection switching valve on bank 1 is stuck in the open position.

Symptoms

  • Check engine light
  • Failed emissions test
  • Noise from air injection system

Common causes

  • Carbon deposits in valve
  • Failed diaphragm
  • Broken valve spring
  • Vacuum supply issue

Diagnostic steps

  1. Inspect valve operation
  2. Check vacuum supply
  3. Listen for air injection noise at idle

Repair notes

Replace secondary air switching valve.

Other Powertrain codes on this vehicle

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