Powertrain
generic / SAE
P0507
Idle Air Control System RPM Higher Than Expected
Idle RPM exceeds the target despite the IAC commanded fully closed. Almost always caused by a vacuum leak that lets air bypass the IAC — torn intake hose, leaking PCV, brake booster, or intake manifold gasket.
SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number5 / 07
Possible causes
- Vacuum leak bypassing IAC high
- PCV valve stuck open medium
- Brake booster diaphragm leaking medium
Symptoms
- Check engine light on
- Idle speed too high, too low, or unstable
- Possible stalling at idle or after cold start
Inspection / repair
- Difficulty: medium
- DIY: possible
- Estimated cost: 20–600 €
- Estimated time: 0.3–4 h
- Component: intake manifold
- Component: pcv valve
- Component: brake booster
- Component: vacuum hose
- MIL / check engine light
- emissions-relevant
- drive cycle required
Sources
References
sae:J2012