Powertrain
generic / SAE
P0508
Idle Air Control System Circuit Low
The control line to the idle air control valve - which opens a small bypass around the throttle to set idle airflow - is shorted to ground or measures a voltage below the plausible level.
SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number5 / 08
Possible causes
- Control line shorted to ground high
- IAC solenoid internally shorted medium
- Connector pins corroded - high contact resistance low
Symptoms
- Check engine light on
- Idle speed too high, too low, or unstable
- Possible stalling at idle or after cold start
Inspection / repair
- Difficulty: easy
- DIY: possible
- Estimated cost: 80–320 €
- Estimated time: 0.4–1.5 h
- Component: idle air control valve
- Component: iac wiring
- MIL / check engine light
Sources
References
sae:J2012