Engine Error
P0506
Idle Control System RPM Lower Than Expected
Severity
Medium
Symptoms
Engine stalls when stopping, low idle speed, rough idle
Common Causes
- Clogged Idle Air Control (IAC) valve
- Extremely dirty throttle body
- Restricted air intake
- Parasitic drag on engine (e.g., bad alternator bearing)
How to Fix
- 1 Thoroughly clean the throttle body
- 2 Replace IAC valve if cleaning fails
- 3 Check and replace air filter
- 4 Inspect engine accessories for binding
Estimated Repair Cost
USD
$50
–
$300
Throttle body cleaning: $80; IAC Valve: $150 - $300