P0505
Idle Air Control System
2018-2018 Audi A6 3.0L Supercharged V6
Moderate SeverityPowertrainGeneric (SAE)
The 2018 Audi A6 is equipped with a 3.0L V6 engine. Below you'll find detailed p0505 diagnostic code information including labor time estimates, cost ranges, and technician notes specific to this engine configuration.
Description
Malfunction in the idle air control (IAC) system.
Symptoms
- Erratic idle speed
- High idle
- Low idle
- Stalling at idle
- Fluctuating RPM
Common Causes
- Faulty IAC valve
- Carbon buildup in IAC or throttle body
- Vacuum leak
- PCM issue
Diagnostic Steps
- Clean IAC valve and passages
- Clean throttle body
- Test IAC valve operation
- Check for vacuum leaks
- Monitor idle RPM with scan tool
Repair Notes
Clean IAC valve and throttle body first. Replace IAC if cleaning fails.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0011Intake Camshaft Position Timing Over-Advanced Bank 1
- P0012Intake Camshaft Position Timing Over-Retarded Bank 1
- P0013Exhaust Camshaft Position Actuator Circuit/Open Bank 1
- P0014Exhaust Camshaft Position Timing Over-Advanced Bank 1
- P0015Exhaust Camshaft Position Timing Over-Retarded Bank 1
P0505 on Other Vehicles
Common Questions
What does code P0505 mean on a 2018-2018 Audi A6?
P0505 stands for "Idle Air Control System". Malfunction in the idle air control (IAC) system.
What are the symptoms of P0505 on a Audi A6?
Common symptoms of P0505 include: Erratic idle speed, High idle, Low idle, Stalling at idle, Fluctuating RPM.
What causes P0505 on a 2018-2018 Audi A6?
Common causes of P0505 include: Faulty IAC valve, Carbon buildup in IAC or throttle body, Vacuum leak, PCM issue.
Last updated: March 2026