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2003 TOYOTA TACOMA
2.7L I4•RWD•AUTOMATIC•gas•3RZ-FE
5 active safety recalls on this vehicle — view recalls
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Repairs0Labor1066Torque2197Fluid17DTC3480Battery2Maintenance0Recalls5
P0511moderate severityPowertrain

Idle Air Control Valve Circuit

on 2003 Toyota Tacoma 2.7L I4 · RWD

What this code means

There is a fault in the idle air control valve circuit. The PCM cannot properly manage engine idle airflow.

Symptoms

  • Rough or unstable idle
  • Stalling at idle
  • Check engine light on

Common causes

  • Faulty idle air control valve
  • Carbon buildup in IAC passage
  • Wiring or connector fault
  • Bad PCM

Diagnostic steps

  1. Read code and observe idle behavior
  2. Inspect IAC wiring and connector
  3. Clean or test IAC valve
  4. Replace IAC valve and retest
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Other Powertrain codes on this vehicle

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