P0506moderate severityPowertrain
Idle Air Control System RPM Lower Than Expected
on 2000 Volvo S80 2.9L I6 · AWD
What this code means
The idle speed is consistently below the target RPM.
Symptoms
- Low idle speed
- Stalling
- Rough idle
Common causes
- Carbon buildup in throttle body
- Vacuum leak
- Faulty IAC valve
- Low fuel pressure
- EGR valve stuck open
Diagnostic steps
- Clean throttle body
- Check for vacuum leaks
- Test IAC valve
- Test fuel pressure
- Check EGR valve
Repair notes
Clean throttle body and IAC. Check for vacuum leaks.
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Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1