# P0505 — Idle Air Control System

> ClearTheCode diagnostic code reference (not OEM service data).

Source: https://clearthecode.com/codes/P0505

**System:** Powertrain · Idle Control

**Severity:** minor

## Description

IAC valve issue. Clean the IAC and throttle body; replace IAC if cleaning doesn't restore stable idle.

## Diagnostic snapshot

- **Difficulty:** 6/10 — Intermediate diagnostics
- **Est. repair cost:** $120 – $450

## Diagnostic workflow

1. Confirm P0505 with a live scan — note pending vs stored and freeze frame data.
2. Inspect wiring/connectors and related sensors before replacing modules.
3. Clear codes and road-test; re-scan after two drive cycles if the monitor must set.

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