P0505

Idle Air Control System Malfunction

Q: What does fault code P0505 mean?

Idle Air Control System Malfunction. The ECM has detected that the actual RPM from the idle air control system deviates from the target idle speed beyond the allowable range.

Q: What are the possible causes of P0505?

Idle air control valve (IACV) dirty or stuck; Throttle body severe carbon buildup; Intake air leak; IACV circuit fault.

Severity: Medium Vehicle Speed & Idle Generic Code

Detailed Description

The ECM has detected that the actual RPM from the idle air control system deviates from the target idle speed beyond the allowable range.

Possible Causes

Idle air control valve (IACV) dirty or stuck

Throttle body severe carbon buildup

Intake air leak

IACV circuit fault.

Solutions & Repair Guide

Clean the throttle body and idle air passages (very common cause); Check if the IACV can move freely; Check intake air piping for sealing; Perform idle learning reset after cleaning.

Disclaimer: The information above is for reference only and does not constitute professional repair advice. Actual causes may vary depending on vehicle make, model, year, and configuration. Always consult a qualified technician for accurate diagnosis.