P0505

P0505 means: Idle Air Control System Malfunction. The idle air control (IAC) system is not functioning properly. This affects idle speed control.

Idle Air Control System Malfunction

The idle air control (IAC) system is not functioning properly. This affects idle speed control.

SeverityModerate

CategoryEngine

Est. Repair Cost$50–$300

Code TypePowertrain

DIY RepairYes

💡 Pro Tip: Clean the IAC with throttle body cleaner — do not use brake cleaner as it can damage the IAC motor.

Full Repair Estimate

$50–$300

DIY Possible?

YES

Severity

Moderate

What does OBD2 code P0505 mean?+

P0505 stands for Idle Air Control System Malfunction. The idle air control (IAC) system is not functioning properly. This affects idle speed control.

What causes code P0505?+

Dirty or stuck IAC valve; Carbon buildup in throttle body; Vacuum leak; Faulty IAC motor

How do I fix code P0505?+

Clean throttle body and IAC passage; Clean or replace IAC valve; Check for vacuum leaks; Perform idle relearn procedure

How much does it cost to fix P0505?+

Estimated repair cost for P0505 is $50–$300.

Is P0505 DIY-friendly?+

Yes — P0505 is generally DIY-friendly with basic tools.