P0506
Idle Control System RPM Lower Than Expected
medium
i Description
The engine idle speed is lower than the ECU target and the system cannot bring it up to the desired RPM.
? Common Causes
- Vacuum leak
- Carbon build-up in throttle body or IAC
- Faulty IAC valve
- Low engine compression
- EGR valve stuck open
! Symptoms
- Low idle RPM
- Engine may stall
- Rough idle
- Check engine light
# Diagnostic Steps
- Clean throttle body and IAC valve
- Check for vacuum leaks
- Test IAC valve operation
- Check EGR valve
- Perform idle relearn procedure
⚙ Typical Fix
Clean the throttle body and IAC valve. Repair vacuum leaks.
Parts Needed
IAC valve, Throttle body cleaner
Estimated Cost
$50-$300
↔ Related Codes
Q Frequently Asked Questions
Yes, but the engine may stall at idle. Keep RPMs up at stops if needed.
☞ Learn More
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