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P0505Severity: Medium

P0505 – Idle Air Control System

Idle speed control (IAC) is not working as expected.

What it means

The ECU cannot regulate idle speed. A dirty idle air control (IAC) valve or carbon on the throttle body are common causes.

Symptoms

  • Rough/surging idle
  • Stalling
  • High or low idle
  • Hard starting

Common causes

  • Dirty throttle body/IAC valve
  • Vacuum leak
  • Faulty IAC motor
  • Wiring issue

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Frequently asked questions

What does trouble code P0505 mean?

P0505 – Idle Air Control System. The ECU cannot regulate idle speed. A dirty idle air control (IAC) valve or carbon on the throttle body are common causes.

Can I drive with a P0505 code?

You can usually drive short distances, but it's best to have it checked before it gets worse.

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